778 research outputs found
Local information transfer as a spatiotemporal filter for complex systems
We present a measure of local information transfer, derived from an existing
averaged information-theoretical measure, namely transfer entropy. Local
transfer entropy is used to produce profiles of the information transfer into
each spatiotemporal point in a complex system. These spatiotemporal profiles
are useful not only as an analytical tool, but also allow explicit
investigation of different parameter settings and forms of the transfer entropy
metric itself. As an example, local transfer entropy is applied to cellular
automata, where it is demonstrated to be a novel method of filtering for
coherent structure. More importantly, local transfer entropy provides the first
quantitative evidence for the long-held conjecture that the emergent traveling
coherent structures known as particles (both gliders and domain walls, which
have analogues in many physical processes) are the dominant information
transfer agents in cellular automata.Comment: 12 page
Екологічна структура тваринного населення Байрака Яцево Яр
The results of the soil animal community investigation in the ravine Yatsev Yar are presented. The connection between ecological structure of animal communities and properties of the corresponding forest types has been shown. Приведены результаты исследования животного населения почв оврага Яцив Яр. Показана связь между свойствами экологической структуры группировок животных и особенностями соответствующих типов лесных екосистемНаведено результати дослідження тваринного населення ґрунтів байраку Яців Яр. Показано зв’язок між властивостями екологічної структури угруповань тварин і особливостями відповідних типів лісових біогеоценозі
Ecological structure of the spider community in the voiskovoy ravine
Приведены результаты исследования экологической структуры пауков оврага Военный (Днепропетровская область). Показана связь между свойствами экологической структуры сообществ пауков и особенностями типов байрачных лесных биогеоценозов.Наведено результати дослідження екологічної структури павуків байраку Військовий (Дніпропетровська область). Показано зв’язок між властивостями екологічної структури угруповань павуків та особливостями типів байрачних лісових біогеоценозів.Research results of the spider community ecological structure in the Voiskovoy ravine are presented. The connection between ecological structure of the community and properties of the corresponding ravine forest types is shown
Екологічне різноманітність і організація тваринного населення байрака Яцево Яр
Characteristics of the ecological structure are shown to be a basis for assessing the indices of the ecological and taxonomic diversity and organisation. The diversity is a condition of the organisation processes in the community. The factors determining the community organisation are internal system interactions and environmental impact. Показано, что характеристики еклогичнои структуры оказывают основу для установления индексов экологического и таксономического разнообразия и организации. Многообразие формирует предпосылки для организационных процессов в группировке. Факторами, определяющими организацию группировки, является внутрисистемные взаимодействия и влияние внешней среды.Показано, що характеристики еклогічної структури надають основу для встановлення індексів екологічного та таксономічного різноманіття та організації. Різноманіття формує передумову для організаційних процесів в угрупованні. Факторами, що визначають організацію угруповання, є внутрішньосистемні взаємодії та вплив зовнішнього середовища.
Перестройка микрополосковых резонаторов СВЧ без ухудшения добротности
Розглянуто шлейфовий і кільцевий мікросмужні резонатори з мікромеханічним перелаштуванням. Показані основні відмінності мікромеханічного методу перелаштування резонансної частоти від інших існуючих методів, а також їх недоліки і переваги. Приведені розрахункові та експериментальні залежності резонансної частоти резонаторів від величини повітряного проміжку між сигнальним електродом та підкладкою, а також експериментальні та теоретичні залежності для власної добротності шлейфового резонатора. Розглянуті залежності діелектричних втрат та втрат у металічних частинах мікромужкового резонатора від величини нормованого повітряного проміжку. Розглянута оцінка похибки вимірювань для приведених експериментальних даних.Stub and ring resonators with resonance frequency micromechanical tuning are presented. Benefits and main differences of micromechanical resonance frequency tuning method from other methods are shown. Normalized dependences of effective permittivity on normalized air gap values for various microstrip line electrode width to substrate height ratios are obtained. Effective permittivity analytical formulas for the case of infinitely wide electrodes are derived. Calculated and experimental dependences of resonance frequency on air gap value and stub experimental unloaded quality factor dependences are given. Air gap influence on resonance frequency value depending on substrate permittivity is shown in terms of the resonance frequency sensitivity. Error estimation for measured experimental data is presented.
Adding tunable heterogeneity between the microstrip resonator signal electrode and the substrate provides not only the resonance frequency tuning but preserves unloaded quality factor. The preservation of the unloaded quality factor during the resonance frequency tuning achieved due to the metal and dielectric loss reduction. Air gap doesn’t have dissipative losses and has permittivity of one, which makes it the best solution for unloaded quality factor preservation. Another important conclusion is that insertion of the air heterogeneity reduces values of dielectric and metal losses arising when substrates with high permittivity are used. For dielectric loss reduction, it is important to maintain low ratio of microstrip line width to substrate height. In contrast to dielectric losses for metal loss reduction the ratio of microstrip line width to substrate height should be high. However, that ratio is limited by impedance permissible range.Представлены шлейфовый и кольцевой резонаторы с микромеханическим управлением. Показаны основные отличия микромеханического метода перестройки резонансной частоты от других существующих методов, а так же их недостатки и преимущества. Приведены расчетные и экспериментальные зависимости резонансной частоты резонаторов от величины воздушного зазора между сигнальным электродом и подложкой, а также экспериментальные зависимости для собственной добротности шлейфового резонатора. Рассмотрены зависимости диэлектрических потерь и потерь в металлических частях микрополоскового резонатора от величины нормированного воздушного зазора. Представлена оценка погрешности измерений для приведенных экспериментальных данных
Smart systems as one of the main components of energy for sustainable development
Розглянуто особливості реалізації концепції Smart Grid за кордоном. Наведено науково-технічні досягнення спеціалістів Національного технічного університету України «Київський політехнічний інститут» у сфері інтелектуалізації електроенергетики. Охарактеризовано основні напрямки побудови Smart систем як однієї із основних складових сталого розвитку енергетики.The features of the concept of Smart Grid abroad. The scientific and technological achievements of specialists of the National Technical University of Ukraine "Kyiv Polytechnic Institute" in the intellectualization of electricity. The basic directions of building Smart Systems as one of the key components of sustainable energy.Рассмотрены особенности реализации концепции Smart Grid за рубежом. Приведены научно-технические достижения специалистов национального технического университета Украины «Киевский политехнический институт» в сфере интеллектуализации электроэнергетики. Охарактеризованы основные направления построения Smart систем как одного из основных составляющих устойчивого развития энергетики
Structure of litter macrofauna communities in poplar plantations in an urban ecosystem in Ukraine
The litter macrofauna of 8 plantations of Populus italica (Du Roi) Moench, P. deltoides Marsh. and P. alba L. was studied in the city of Dnipro. The invertebrates were taken by manual sifting of litter from experimental plots of 8 m2. The total number of litter macrofauna in the poplar plantations varied from 8 to 187 specimen/m2, on average 53 specimen/m2. The greatest variety of species was obtained from a white poplar plantation with common hop and an elm-poplar plantation with bare soil and Amorpha fruticosa L. bushes (15 and 9 species correspondingly). The ma ximum readings on the Shannon–Weaver diversity index come from the abovementioned areas (3.2 and 2.9 bits respectively). The highest number of zoophages (40%) was obtained from the white poplar plantation with common hop. There was great consistency in the species composition across the plots, with the same 60 species (more than 50% of the total number of species of litter macrofauna recorded in the study) being found in 7 out of the 8 study plots. The share of species rare for any given ecosystem exceeded 10% in only 2 out of the 8 plantations studied. The dominant group in the size structure of the litter macrofauna of the poplar plantations (44–96%) was invertebrates of 4–7 mm length. In 5 out of 8 poplar plantations no species over 15 mm in length were found. This indicates the degraded size structures of the litter macrofauna communities. In taxonomic structure the dominant groups were Formicidae, Pulmonata, Porcellionidae, Lygaeidae, Julidae, Silphidae, Araneae, Carabidae, Staphylinidae. The results obtained indicate the low variety and degradation of the trophic and size structure of the litter macrofauna of these urban poplar plantations, which are subject to lack of moisture. The litter macrofauna of 8 plantations of Populus italica (Du Roi) Moench, P. deltoides Marsh. and P. alba L. was studied in the city of Dnipro. The invertebrates were taken by manual sifting of litter from experimental plots of 8 m2. The total number of litter macrofauna in the poplar plantations varied from 8 to 187 specimen/m2, on average 53 specimen/m2. The greatest variety of species was obtained from a white poplar plantation with common hop and an elm-poplar plantation with bare soil and Amorpha fruticosa L. bushes (15 and 9 species correspondingly). The maximum readings on the Shannon–Weaver diversity index come from the abovementioned areas (3.2 and 2.9 bits respectively). The highest number of zoophages (40%) was obtained from the white poplar plantation with common hop. There was great consistency in the species composition across the plots, with the same 60 species (more than 50% of the total number of species of litter macrofauna recorded in the study) being found in 7 out of the 8 study plots. The share of species rare for any given ecosystem exceeded 10% in only 2 out of the 8 plantations studied. The dominant group in the size structure of the litter macrofauna of the poplar plantations (44–96%) was invertebrates of 4–7 mm length. In 5 out of 8 poplar plantations no species over 15 mm in length were found. This indicates the degraded size structures of the litter macrofauna communities. In taxonomic structure the dominant groups were Formicidae, Pulmonata, Porcellionidae, Lygaeidae, Julidae, Silphidae, Araneae, Carabidae, Staphylinidae. The results obtained indicate the low variety and degradation of the trophic and size structure of the litter macrofauna of these urban poplar plantations, which are subject to lack of moisture. The litter macrofauna of 8 plantations of Populus italica (Du Roi) Moench, P. deltoides Marsh. and P. alba L. was studied in the city of Dnipro. The invertebrates were taken by manual sifting of litter from experimental plots of 8 m2. The total number of litter macrofauna in the poplar plantations varied from 8 to 187 specimen/m2, on average 53 specimen/m2. The greatest variety of species was obtained from a white poplar plantation with common hop and an elm-poplar plantation with bare soil and Amorpha fruticosa L. bushes (15 and 9 species correspondingly). The maximum readings on the Shannon–Weaver diversity index come from the abovementioned areas (3.2 and 2.9 bits respectively). The highest number of zoophages (40%) was obtained from the white poplar plantation with common hop. There was great consistency in the species composition across the plots, with the same 60 species (more than 50% of the total number of species of litter macrofauna recorded in the study) being found in 7 out of the 8 study plots. The share of species rare for any given ecosystem exceeded 10% in only 2 out of the 8 plantations studied. The dominant group in the size structure of the litter macrofauna of the poplar plantations (44–96%) was invertebrates of 4–7 mm length. In 5 out of 8 poplar plantations no species over 15 mm in length were found. This indicates the degraded size structures of the litter macrofauna communities. In taxonomic structure the dominant groups were Formicidae, Pulmonata, Porcellionidae, Lygaeidae, Julidae, Silphidae, Araneae, Carabidae, Staphylinidae. The results obtained indicate the low variety and degradation of the trophic and size structure of the litter macrofauna of these urban poplar plantations, which are subject to lack of moisture.
Quality management principles of scientific and methodological support for students’ activity within e-learning environment
The article highlights the quality management principles of scienti c and methodological support for learners 'activity in the Russian univer-sity e-learning environmen
RESEARCH OF DYNAMIC CHARACTERISTICS OF INDUCTION MOTORS IN ELECTRIC DRIVES WITH MATCHING TRANSFORMER AND REDUCER
Introduction. The variety of electric drives, the performance characteristics of which correspond to the set requirements of consumers while ensuring reliable and economical operation for a certain time resource, characterizes the variety of circuit solutions, including using matching transformers and reducers. Problem. The use of matching transformers and reducers units significantly changes the performance characteristics of the electric drive. Most articles are devoted to modeling an electric drive without such elements. It is advisable to consider simulations of electric drives using these elements. Methodology. In the models of matching transformers and reducers, the initial data are used, which determine both the functional properties and the mass and size parameters. The latter provide an opportunity to consider the economic aspects of the electric drive. For the correct calculation of the energy balance of the electric drive, the efficiency of the elements under consideration is taken into account. Results. The use of the developed algorithms for modeling the dynamic modes of two induction motors in electric drives operating on a specific load diagram, with the connection of a matching transformer and reducers, is considered. Dependencies of efficiency and power factor of motors have allowed to determine the medium cyclic energy indicators. The mass- size and cost indicators of variants of electric drives were found, which made it possible to calculate the average cyclic reduced costs of electric drives. Practical value. The possibility of choosing the best variant of the drive based on various indicators, including the minimum amount of energy losses per year, is substantiated
Peculiarities of the stochastic motion in antiferromagnetic nanoparticles
Antiferromagnetic (AFM) materials are widely used in spintronic devices as
passive elements (for stabilization of ferromangetic layers) and as active
elements (for information coding). In both cases switching between the
different AFM states depends in a great extent from the environmental noise. In
the present paper we derive the stochastic Langevin equations for an AFM vector
and corresponding Fokker-Planck equation for distribution function in the phase
space of generalised coordinate and momentum. Thermal noise is modeled by a
random delta-correlated magnetic field that interacts with the dynamic
magnetisation of AFM particle. We analyse in details a particular case of the
collinear compensated AFM in the presence of spin-polarised current. The energy
distribution function for normal modes in the vicinity of two equilibrium
states (static and stationary) in sub- and super-critical regimes is found. It
is shown that the noise-induced dynamics of AFM vector has pecuilarities
compared to that of magnetisation vector in ferromagnets.Comment: Submitted to EPJ ST, presented at the 4-th Conference on Statistical
Physics, Lviv, Ukraine, 201
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