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Time-domain Li-ion Battery Modeling under Staircase Charging and Discharging

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Time-domain Li-ion Battery Modeling under Staircase Charging...

2021 International Conference on Microelectronics, ICM 2021

作者： Abdelhafiz, Shahenda M. Abdelaty, A.M. Fouda, M.E. Radwan, A.G. Giza Egypt Fayoum University Faculty of Engineering Engineering Mathematics and Physics Dept. Egypt Cairo University Faculty of Engineering Engineering Mathematics and Physics Dept. Egypt University of California-Irvine Electrical Engineering and Computer Science Dept. Irvine United States School of Engineering and Applied Sciences Nile University Giza Egypt

ISBN: (纸本)9781665408394

Parameter identification of Li-ion battery models is important for efficiently charge and discharge the most widely used energy storage devices. In this work, we propose a simplified battery model with a parameter identification method for time-domain charging and discharging. Staircase PotentioElectrochemical Impedance Spectroscopy technique (SPEIS) is chosen to characterize the batteries during charging and discharging cycles at different voltage steps values. Marine Predator Algorithm (MPA) is used to identify the proposed model parameters on two commercial Li-ion coin-shaped batteries. The proposed model shows very good matching with the experiments with absolute current error less than 10 4. Hence, the proposed model can be used for real-time applications to predict the battery's behavior under different operating conditions. © 2021 IEEE.

关键词： Lithium-ion batteries

Universality of Top Rank Statistics for Brownian Reshuffling

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arXiv 2024年

作者： Burda, Zdzislaw Kieburg, Mario AGH University of Krakow Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Kraków30-059 Poland University of Melbourne School of Mathematics and Statistics 813 Swanston Street Parkville MelbourneVIC3010 Australia Institut Mittag-Leffler DjursholmSE-182 60 Sweden

We study the dynamical aspects of the top rank statistics of particles, performing Brownian motions on a half-line, which are ranked by their distance from the origin. For this purpose, we introduce an observable that we call the overlap ratio Ω(t), whose average is the probability that a particle that is on the top-n list at some time will also be on the top-n list after time t. The overlap ratio is a local observable which is concentrated at the top of the ranking and does not require the full ranking of all particles. It is simple to measure in practice. We derive an analytical formula for the average overlap ratio for a system of N particles in the stationary state that undergo independent Brownian motion on the positive real half-axis with a reflecting wall at the origin and a drift towards the wall. In particular, we show that for N → ∞, the overlap ratio takes a rather simple form 〈Ω(t)〉 = erfc(a√t) for n 1 with some scaling parameter a > 0. This result is a very good approximation even for moderate sizes of the top-n list such as n = 10. Moreover, as we show, the overlap ratio exhibits universal behavior observed in many dynamical systems including geometric Brownian motion, Brownian motion with a position-dependent drift and a soft barrier on one side, the Bouchaud-Mézard wealth distribution model, and Kesten processes. © 2024, CC BY.

关键词： Brownian movement

Time-adjusted analysis shows weak associations between BCG vaccination policy and COVID-19 disease progression 21

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Time-adjusted analysis shows weak associations between BCG v...

21st Conference Information Technologies - Applications and Theory, ITAT 2021

作者： Bod’ová, Katarína Boža, Vladimír Brejová, Broňa Kollár, Richard Mikušová, Katarína Vinař, Tomáš Department of Mathematical Analysis and Numerical Mathematics Faculty of Mathematics Physics and Informatics Comenius University Mlynská dolina Bratislava842 48 Slovakia Department of Applied Informatics Faculty of Mathematics Physics and Informatics Comenius University Mlynská dolina Bratislava842 48 Slovakia Department of Computer Science Faculty of Mathematics Physics and Informatics Comenius University Mlynská dolina Bratislava842 48 Slovakia Department of Applied Mathematics and Statistics Faculty of Mathematics Physics and Informatics Comenius University Mlynská dolina Bratislava842 48 Slovakia Department of Biochemistry Faculty of Natural Sciences Comenius University Ilkovičova 6 Bratislava842 48 Slovakia

In this study, we ascertain the associations between BCG vaccination policies and the disease progression in the initial phases of COVID-19 pandemics through analysis of various time-adjusted indicators either directly extracted from the incidence and death reports, or estimated as parameters of disease progression models. We observe weak correlation between BCG vaccination status and indicators related to disease reproduction characteristics. We did not find any associations with case fatality rates (CFR), but the differences in CFR estimates were likely dominated by differences in testing and case reporting between countries. Copyright © 2021 for this paper by its authors.

关键词： Cell proliferation

Multiple Defect States Engineering Towards High Thermoelectric Performance in Gete-Based Materials

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SSRN

SSRN 2024年

作者： Parashchuk, Taras Wiendlocha, Bartlomiej Cherniushok, Oleksandr Pryga, Kacper Ciesielski, Kamil Toberer, Eric Wojciechowski, Krzysztof T. AGH University of Krakow Faculty of Materials Science and Ceramics Department of Inorganic Chemistry Thermoelectric Research Laboratory Mickiewicza Ave. 30 Krakow30-059 Poland AGH University of Krakow Faculty of Physics and Applied Computer Science Mickiewicza Ave. 30 Krakow30-059 Poland Colorado School of Mines Department of Physics GoldenCO80401 United States AGH University of Krakow Centre of Energy Laboratory of Thermoelectric Technologies Mickiewicza Ave. 30 Krakow30-059 Poland

GeTe is a promising material for thermoelectric (TE) applications. However, its low Seebeck coefficient and high thermal conductivity in the mid-temperature range of 298-550 K have hindered its widespread use in TE devices. In this work, we show that a combination of resonant-like behavior, Fermi level tuning, and miscibility gap exploration can significantly improve the energy conversion performance of GeTe. The resonant-like hump in GeTe is induced by Ga doping, while Bi provides the optimized carrier concentration and induces band convergence. The synergistic effects of Bi and Ga significantly improve the Seebeck coefficient from 38 µVK-1 for undoped GeTe to over 120 µVK-1 for Bi and Ga-containing materials at 298 K and provide a high power factor over a wide temperature range. Phonon scattering is strengthened by optimizing the microstructure through Pb-induced spinodal decomposition, resulting in a very low lattice thermal conductivity of approximately 0.5 Wm-1K-1 at 600 K for the triple-doped samples. The improved power factor and reduced lattice thermal conductivity resulted in a significant increase in the maximum thermoelectric figure of merit ZT, reaching 2.1 at 600 K for the Ge0.87Pb0.05Bi0.06Ga0.02Te sample. Additionally, the average figure of merit ZTave for this sample achieved an outstanding value of 1.4 for Ge0.87Pb0.05Bi0.06Ga0.02Te at a temperature gradient of 475 K (Tc = 298 K). The developed material shows great potential for use in energy conversion devices, with an estimated energy conversion efficiency exceeding 17%. © 2024, The Authors. All rights reserved.

关键词： Germanium alloys

Magnetotransport Signatures of the Radial Rashba Spin-Orbit Coupling in Proximitized Graphene

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arXiv 2024年

作者： Kang, Wun-Hao Barth, Michael Garcia-Ruiz, Aitor Mreńca-Kolasińska, Alina Liu, Ming-Hao Kochan, Denis Department of Physics National Cheng Kung University Tainan70101 Taiwan National Cheng Kung University Tainan70101 Taiwan Institute for Theoretical Physics University of Regensburg Regensburg93040 Germany National Graphene Institute University of Manchester ManchesterM13 9PL United Kingdom AGH University Faculty of Physics and Applied Computer Science Kraków30-059 Poland Institute of Physics Slovak Academy of Sciences Bratislava84511 Slovakia

Graphene-based van der Waals heterostructures take advantage of tailoring spin-orbit coupling (SOC) in the graphene layer by proximity effect. At long-wavelength—saddled by the electronic states near the Dirac points—the proximitized features can be effectively modeled by the Hamiltonian involving novel SOC terms and allow for an admixture of the tangential and radial spin textures—by the so-called Rashba angle θR. Taking such effective models we perform realistic large-scale magneto-transport calculations—transverse magnetic focusing and Dyakonov-Perel spin relaxation—and show that there are unique qualitative and quantitative features allowing for an unbiased experimental disentanglement of the conventional Rashba SOC from its novel radial counterpart, called here the radial Rashba SOC. Along with that, we propose a scheme for a direct estimation of the Rashba angle by exploring the magneto-response symmetries when swapping an in-plane magnetic field. To complete the story, we analyze the magneto-transport signatures in the presence of an emergent Dresselhaus SOC and also provide some generic ramifications about possible scenarios of the radial superconducting diode effect. © 2024, CC0.

关键词： Magnetos

Higher order cumulants of transverse momentum and harmonic flow in relativistic heavy ion collisions

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arXiv 2021年

作者： Bożek, Piotr Samanta, Rupam AGH University of Science and Technology Faculty of Physics and Applied Computer Science aleja Mickiewicza 30 Cracow30-059 Poland

Higher order symmetric cumulants of global collective observables in heavy ion collisions are studied. The symmetric cumulants can be straightforwardly constructed for scalar observables: the average transverse momentum, the multiplicity, and the squares of harmonic flow vectors. Third and fourth order cumulants are calculated in the hydrodynamic model. A linear predictor of the average transverse momentum and harmonic flow coefficients in a collision is used to predict the values of the cumulants from the moments of the initial distribution. The symmetric cumulants divided by the averages (or the standard deviations) of the considered observables can be used as a fine tool to study correlations present in the initial state of the collision. © 2021, CC BY.

关键词： Heavy ions

Electronic structure, electron-phonon coupling and superconductivity in noncentrosymmetric ThCoC2 from ab initio calculations

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arXiv 2021年

作者： Kuderowicz, Gabriel Wójcik, Pawel Wiendlocha, Bartlomiej Faculty of Physics and Applied Computer Science AGH University of Science and Technology Aleja Mickiewicza 30 Krakow30-059 Poland

Superconductors without inversion symmetry in their crystal structure are known to exhibit unconventional properties. Recently, based on the measured temperature dependence of the magnetic field penetration depth, superconductivity in noncentrosymmetric ThCoC2 was proposed to be a nodal d-wave and mediated by the spin fluctuations. Moreover, a non-BCS behavior of the temperature dependence of the electronic specific heat and the magnetic upper critical field were reported. In this work, the electronic structure, phonons and electron-phonon coupling are studied in ThCoC2 on the basis of ab initio computations. The effect of the spin-orbit coupling on the electronic structure and electron-phonon interaction is analyzed, and a large splitting of the electronic band structure is found. The calculated electron-phonon coupling constant λ = 0.59 remains in decent agreement with the experimental estimates, suggesting that the electron-phonon interaction is strong enough to explain superconductivity with Tc 2.5 K. Nevertheless, we show that the conventional isotropic Eliashberg formalism is unable to describe the thermodynamic properties of the superconducting state, as calculated temperature dependence of the electronic specific heat and magnetic penetration depth deviate from experiments, which is likely driven by the strong spin-orbit coupling and inversion symmetry breaking. In addition, to shed more light on the pairing mechanism, we propose to measure the carbon isotope effect, as our calculations based on the electron-phonon coupling predict the observation of the isotope effect with an exponent α 0.15. Copyright © 2021, The Authors. All rights reserved.

关键词： Electron-phonon interactions

Invariants and Reversibility In Polynomial Systems of Ode

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SSRN

SSRN 2024年

作者： Grašič, Mateja Jarrah, Abdul Salam Romanovski, Valery G. Faculty of Natural Science and Mathematics University of Maribor Koroška Cesta 160 MariborSI-2000 Slovenia Institute of Mathematics Physics and Mechanics Jadranska 19 LjubljanaSI-1000 Slovenia Department of Mathematics and Statistics American University of Sharjah Sharjah United Arab Emirates Faculty of Electrical Engineering and Computer Science University of Maribor Koroška cesta 46 MariborSI-2000 Slovenia Center for Applied Mathematics and Theoretical Physics Mladinska 3 MariborSI-2000 Slovenia

This paper explores a relationship between invariants of certain group actions and the time-reversibility of two-dimensional polynomial differential systems exhibiting a $1:-1$ resonant singularity. We focus on the connection of time-reversibility with the Sibirsky subvariety of the center variety, which encompasses systems possessing a local analytic first integral near the origin. An algorithm for generating the Sibirsky ideal for these systems is proposed and the algebraic properties of the ideal are examined. Furthermore, using a generalization of the concept of time-reversibility we study $n$-dimensional systems with a $1:\zeta:\zeta^2:\dots:\zeta^{n-1}$ resonant singularity, where $n$ is prime and $\zeta$ is a primitive $n$-th root of unity. We study the invariants of a Lie group action on the parameter space of the system, leveraging the theory of binomial ideals as a fundamental tool for the analysis. Our study reveals intriguing connections between generalized reversibility, invariants, and binomial ideals, shedding light on their complex interrelations. © 2024, The Authors. All rights reserved.

关键词： Choquet integral

Phase Separation in PCDTBT:PCBM Blends:from Flory-Huggins Interaction Parameters to Ternary Phase Diagrams

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Chinese Journal of Polymer science 2020年第9期38卷 1025-1033,I0009页

作者： Monika Biernat Pawel Dabczynski Pawel Biernat Jakub Rysz Jagiellonian University Faculty of Physics Astronomy and Applied Computer Science ul.lojasiewicza 1130-348 KrakówPoland Mathematisches Institut Rheinische Friedrich-Wilhelms-Universitat BonnEndenicher Allee 6053115 BonnGermany

The substantial increase in the efficiency of organic solar cells achieved in recent years would not have been possible without work on the synthesis of new materials and understanding the relationship between the morphology and performance of organic photovoltaic *** structure of solvent-cast active layers is a result of phase separation in mixtures of donor and acceptor *** a large extent,this process depends on the interactions between the components of the ***,we present a systematic analysis of the morphology of poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)](PCDTBT)and[6,6]-phenyl-C71-butyric acid methyl ester(PC70BM)films in terms of the ternary phase *** interaction parameters between PCDTBT and four different solvents,namely chloroform,chlorobenzene,o-dichlorobenzene,and toluene,were estimated based on swelling *** on these values,ternary phase diagrams of PCDTBT:PC70BM in different solvents were *** morphology of spin-coated films with different blend ratios cast from different solvents is discussed in terms of the obtained phase diagrams.

关键词： PCDTBT Ternary phase diagrams Interaction parameter Swelling