Results 1 to 10 of about 1,088,123 (148)
CENTER PROBLEM FOR A THIRD-ORDER ODES. [PDF]
Int J Bifurcat Chaos, 2013 We obtain necessary and sufficient conditions for the existence of a center on a local center manifold for three 4-parameter families of quadratic systems on ℝ3. We also give a positive answer to an open question posed in [Dias & Mello, 2010] related to similar systems.
Mahdi A.
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The complete vertex p-center problem [PDF]
EURO Journal on Computational Optimization, 2020 The vertex p-center problem consists of locating p facilities among a set of M potential sites such that the maximum distance from any demand to its closest located facility is minimized.
F.Antonio Medrano
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Structure, Thermal Properties and Proton Conductivity of the Sulfonated Polyphenylquinoxalines
Membranes, 2022 This paper briefly reviews the results of scientific research on the proton conductivity of sulfonated polyphenylquinoxalines. Synthesis, structure (IR spectroscopy, SEM, quantum-chemical modeling, molecular weight distribution), moisture capacity ...
Anna V. Pisareva +9 more
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On the State of Graphene Oxide Nanosheet in a Polyurethane Matrix
Nanomaterials, 2023 Thermally stable films were obtained from a water-based polyurethane (PU) dispersion with small (0.1–1.5 wt.%) additions of graphene oxide (GO).
Sergey A. Baskakov +7 more
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Centers of cubic differential systems with the line at infinity of maximal multiplicity
Acta et Commentationes: Ştiinţe Exacte şi ale Naturii, 2023 We classify all cubic differential systems with a center-focus critical point and the line at infinity of maximal multiplicity. It is proved that the critical point is of the center type if and only if the divergence of the vector field associated to ...
Alexandru Șubă
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Donation Center Location Problem [PDF]
Algorithmica, 2012 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Huang, Chien-Chung, Svitkina, Zoya
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Cyclicity versus Center Problem [PDF]
Qualitative Theory of Dynamical Systems, 2010 We prove that there are one-parameter families of planar differential equations for which the center problem has a trivial solution and on the other hand the cyclicity of the weak focus is arbitrarily high. We illustrate this phenomenon in several examples for which this cyclicity is computed.
Gasull, Armengol, Giné, Jaume
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Monitoring and Forecasting the Dynamics of the Incidence of COVID-19 in Moscow: 2020–2021
Эпидемиология и вакцинопрофилактика, 2022 Relevance. The accumulation of information (statistical data and knowledge) about the COVID-19 pandemic leads to the refinement of mathematical models, to the expansion of the area of their use.
A. V. Sokolov, L. A. Sokolova
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Sociology of knowledge оn the generations formation mechanism [PDF]
Социологический журнал, 2013 Socialization process involves interaction between two generations – prevalent and growing one. The present article demonstrates, that different generations display two various types of rational behavior in terms of intergenerational relations ...
V. M. Pashinskiy
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