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Recent results of zebra patterns in solar radio bursts

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Research in Astronomy and Astrophysics 2010年第9期10卷 821-866页

作者： gennady P.Chernov Key Laboratory of Solar Activity National Astronomical ObservatoryChinese Academy of Science Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences (IZMIRAN)

This review covers the most recent experimental results and theoretical research on zebra patterns （ZPs） in solar radio bursts. The basic attention is given to events with new peculiar elements of zebra patterns received over the last few years. All new properties are considered in light of both what was known earlier and new theoretical models. Large-scale ZPs consisting of small-scale fiber bursts could be explained by simultaneous inclusion of two mechanisms when whistler waves ＂high- light＂ the levels of double plasma resonance （DPR）. A unique fine structure was observed in the event on 2006 December 13： spikes in absorption formed dark ZP stripes against the absorptive type Ⅲ-like bursts. The spikes in absorption can appear in accordance with well known mechanisms of absorptive bursts. The additional injection of fast particles filled the loss-cone （breaking the loss-cone distribution）, and the generation of the continuum was quenched at these moments. The maximum absorptive effect occurs at the DPR levels. The parameters of millisecond spikes are determined by small dimensions of the particle beams and local scale heights in the radio source. Thus, the DPR model helps to understand severai aspects of unusual elements of ZPs. However, the simultaneous existence of several tens of the DPR levels in the corona is impossible for any realistic profile of the plasma density and magnetic field. Three new theories of ZPs are examined. The formation of eigenmodes of transparency and opac- ity during the propagation of radio waves through regular coronal inhomogeneities is the most natural and promising mechanism. Two other models （nonlinear periodic space - charge waves and scattering of fast protons on ion-sound harmonics） could happen in large radio bursts.

关键词： Sun general -- Sun flare -- Sun radio radiation

CRITICAL ISSUES IN THE NUMERICAL TREATMENT OF THE PARAMETER ESTIMATION PROBLEMS IN IMMUNOLOGY

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Journal of Computational Mathematics 2012年第1期30卷 59-79页

作者： Tatyana Luzyanina gennady Bocharov Institute of Mathematical Problems in Biology RAS Pushchino Moscow reg. Russia Institute of Numerical Mathematics RAS Moscow Russia

A robust and reliable parameter estimation is a critical issue for modeling in immunology. We developed a computational methodology for analysis of the best-fit parameter estimates and the information-theoretic assessment of the mathematical models formulated with ODEs. The core element of the methodology is a robust evaluation of the first and second derivatives of the model solution with respect to the model parameter values. The critical issue of the reliable estimation of the derivatives was addressed in the context of inverse problems arising in mathematical immunology. To evaluate the first and second derivatives of the ODE solution with respect to parameters, we implemented the variational equations-, automatic differentiation and complex-step derivative approximation methods. A comprehensive analysis of these approaches to the derivative approximations is presented to understand their advantages and limitations.

关键词： Mathematical modeling in immunology Parameter estimation Constrainedoptimization.

Exploring and visualizing temporal relations in multivariate time series

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Visual Informatics 2023年第4期7卷 57-72页

作者： Gota Shirato Natalia Andrienko gennady Andrienko Fraunhofer IAIS Sankt AugustinGermany University of Bonn BonnGermany City University of LondonLondonUK

This paper introduces an approach to analyzing multivariate time series(MVTS)data through progressive temporal abstraction of the data into patterns characterizing the behavior of the studied dynamic *** paper focuses on two core challenges:identifying basic behavior patterns of individual attributes and examining the temporal relations between these patterns across the range of attributes to derive higher-level abstractions of multi-attribute *** proposed approach combines existing methods for univariate pattern extraction,computation of temporal relations according to the Allen’s time interval algebra,visual displays of the temporal relations,and interactive query operations into a cohesive visual analytics *** paper describes the application of the approach to real-world examples of population mobility data during the COVID-19 pandemic and characteristics of episodes in a football match,illustrating its versatility and effectiveness in understanding composite patterns of interrelated attribute behaviors in MVTS data.

关键词： Temporal relations Temporal abstraction Multivariate time series Time intervals

Identifying,exploring,and interpreting time series shapes in multivariate time intervals

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Visual Informatics 2023年第1期7卷 77-91页

作者： Gota Shirato Natalia Andrienko gennady Andrienko Fraunhofer IAIS Sankt Augustin53757Germany University of Bonn Regina-Pacis-Weg 3Bonn53113Germany City University of LondonNorthampton SquareLondonEC1V 0HBUK

We introduce a concept of episode referring to a time interval in the development of a dynamic phenomenon that is characterized by multiple time-variant attributes.A data structure representing a single episode is a multivariate time *** analyse collections of episodes,we propose an approach that is based on recognition of particular patterns in the temporal variation of the variables within *** episode is thus represented by a combination of *** this representation,we apply visual analytics techniques to fulfil a set of analysis tasks,such as investigation of the temporal distribution of the patterns,frequencies of transitions between the patterns in episode sequences,and co-occurrences of patterns of different variables within same *** demonstrate our approach on two examples using real-world data,namely,dynamics of human mobility indicators during the COVID-19 pandemic and characteristics of football team movements during episodes of ball turnover.

关键词： Temporal patterns Multivariate time series Time intervals

Towards high-performance tubular-type protonic ceramic electrolysis cells with all-Ni-based functional electrodes

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Journal of Energy Chemistry 2020年第1期29卷 65-74,I0003页

作者： Artem Tarutin Anna Kasyanova Julia Lyagaeva gennady Vdovin Dmitry Medvedev Laboratory of Electrochemical Devices Based on Solid Oxide Proton Electrolytes Institute of High Temperature ElectrochemistryYekaterinburg 620137Russia Ural Federal University Yekaterinburg 620002Russia

Protonic ceramic electrolysis cells(PCECs),which permit high-temperature electrolysis of water,exhibit various advantages over conventional solid oxide electrolysis cells(SOECs),including cost-effectiveness and the potential to operate at low-/intermediate-temperature ranges with high performance and *** many efforts have been made in recent years to improve the electrochemical characteristics of PCECs,certain challenges involved in scaling them up remain *** the present work,we present a twin approach of combining the tape-calendering method with all-Ni-based functional electrodes with the aim of fabricating a tubular-designed PCEC having an enlarged electrode area(4.6 cm^2).This cell,based on a 25μm-thick BaCe0.5Zr0.3Dy0.2O3-δ proton-conducting electrolyte,a nickelbased cermet and a Pr1.95Ba0.05NiO4+δ oxygen electrode,demonstrates a high hydrogen production rate(19 m L min^-1 at 600℃),which surpasses the majority of results reported for traditional button-or planar-type *** findings increase the scope for scaling up solid oxide electrochemical cells and maintaining their operability at reducing temperatures.

关键词： Steam electrolysis Hydrogen production PCECs Proton-conducting electrolytes Ln2NiO4

Multi-layered plate finite element models with node-dependent kinematics for smart structures with piezoelectric components

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Chinese Journal of Aeronautics 2021年第8期34卷 164-175页

作者： Guohong LI Erasmo CARRERA Yuliang HOU gennady M.KULIKOV MUL2 Group Department of Mechanical and Aerospace EngineeringPolitecnico di TorinoTorino 10129Italy Laboratory of Intelligent Materials and Structures Tambov State Technical UniversityTambov 392000Russia School of Mechanical and Power Engineering Zhengzhou UniversityZhangzhou 450001China

This article presents a type of plate Finite Element(FE)models with adaptive mathematical refinement capabilities for modeling laminated smart structures with piezoelectric layers or distributed *** p-version shape functions are used in combination with the higher-order Layer-Wise(LW)kinematics adopting hierarchical Legendre ***-Dependent Kinematics(NDK)is employed to implement local LW models in the regions with piezoelectric components and simulate the global substrate structure with the Equivalent Single-Layer(ESL)*** the proposed NDK FE models,the electro-mechanical behavior of smart structures can be predicted with high fidelity and numerical efficiency,and various patch configurations can be conveniently modeled through one set of mesh ***,the effectiveness and efficiency of the NDK FE approach are assessed through numerical examples and its application is demonstrated.

关键词： Finite element Laminated composites Piezoelectric Refined plate theory Smart structures

HOW DOES ANESTHESIA AFFECT VARIOUS LEVELS OF EXPERIMENTAL TRAUMATIC BRAIN INJURY?

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Journal of Innovative Optical Health Sciences 2011年第4期4卷 409-420页

作者： BARBIRO-MICHAELY EFRAT MANOR TAMAR ROGATSKY gennady MAYEVSKY AVRAHAM The Mina and Everard Goodman Faculty of Life-Sciences The Leslie and Susan Gonda Multidisciplinary Brain Research Center Bar-Ilan University Ramat-Gan52900Israel

The use of anesthetics is a well-known treatment for severely injured *** the present study we tested the pathophysiology of several levels of injury damage in a rat model and also tested the effect of Equithesin on brain vitality in these *** Brain Injury(TBI)was induced using thefluid percussion injury model in four levels:mild,moderate and two levels of severe *** real-time evaluation was performed by the multiparametric monitoring assembly(MPA)which enable cerebral bloodflow(CBF)monitoring by laser Dopplerflowmetry,mitochondrial NADH(Nicotinamide adenine dinucleotide)monitoring by thefluorometric technique,ionic homehostasis using special mini-electrodes,intracranial pressure(ICP)by the ICP camino device and needle electrodes for ECoG(Electrocorticogram)*** results showed high correlation between the level of impact and the extent of changes in the physiological properties of the injury as indicated by the changes in all parameters monitored using the MPA ***,Equithesin improved CBF,ionic extracellular level and mitochondrial redox state following mild and moderate TBI while in severe TBI,Equithesin did not improve the metabolic state of the cerebral cortex,although it decreased the mortality rate from 66%to 20%,and following extra-severe TBI level,Equithesin did not improve survival *** conclusion it seems that Equithesin's protective effect exists under mild to moderate levels of injury and not in case of severe injuries.

关键词： Cerebral bloodflow mitochondrial NADH multiparametric monitoring

Electromagnetic Characteristics and Corrosion Resistance of New Magnetosoft Materials Based on Capsulated Iron Powders

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Chemical Research in Chinese Universities 2020年第6期36卷 1326-1331页

作者： Alexander VETCHER gennady GOVOR Olga DEMIDENKO Virgil CONSTANTIN Ana Maria POPESCU Scientific-Practical Materials Research Centre National Academy of BelarusP.Brovki 19 Str.220072 MinskBelarus “IlieMurgulescu”Institute of Physical Chemistry of Romanian Academy Laboratory of Electrochemistry and CorrosionSplaiullndependentei 202Bucharest 060021Romania

A new method of depositing an insulating multifunctional oxide coating on metal particles was *** coatings increase corrosion resistance and insulate metal particles from each *** base of capsulated by oxide coating water-atomized iron powder ASC100.29,new composite soft magnetic materials were synthesized,which are able of replacing electrical steel in ***,electromagnetic properties and corrosion characte-ristics of the obtained composites were *** was found that the synthesized composite materials have low elec-tromagnetic losses,high values of magnetic induction(up to 2.1 T)and good corrosion *** results demon-strate that the use of such materials in power supplies,c hokes,transformers,stators and rotors of electric machines and other products ensures their stable operation under various conditions.

关键词： Soft magnetic composite material Iron powder Insulating cover High-frequency transformer Stators and rotors of electro machine

A theoretical model for pattern discovery in visual analytics

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Visual Informatics 2021年第1期5卷 23-42页

作者： Natalia Andrienko gennady Andrienko Silvia Miksch Heidrun Schumann Stefan Wrobel Fraunhofer Institute IAIS Sankt-AugustinGermany City University of LondonLondonUK TU Wien ViennaAustria University of Rostock RostockGermany University of Bonn BonnGermany

The word‘pattern’frequently appears in the visualisation and visual analytics literature,but what do we mean when we talk about patterns?We propose a practicable definition of the concept of a pattern in a data distribution as a combination of multiple interrelated elements of two or more data components that can be represented and treated as a unified *** theoretical model describes how patterns are made by relationships existing between data *** the types of these relationships,it is possible to predict what kinds of patterns may *** demonstrate how our model underpins and refines the established fundamental principles of *** model also suggests a range of interactive analytical operations that can support visual analytics workflows where patterns,once discovered,are explicitly involved in further data analysis.

关键词： Visual analytics Data distribution Pattern Abstraction Data organisation Data arrangement Data variation Pattern discovery