Results 11 to 20 of about 471,373 (286)
Quadratic Systems with Center and Their Perturbations
Journal of Differential Equations, 1994 By writing the general quadratic system on a plane having a singular point of center or focus type in the complex form (1) \(\dot z= (i+\lambda) z+ Ax^ 2+ Bz\bar z+ C\bar z^ 2\), \(\lambda\in\mathbb{R}\), \(A,B,C\in\mathbb{C}\), \(z= x+iy\), first, the author gives a simple algebraic proof of the classical Dulac and Kapteyn theorem: Theorem 1.
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Research on Strip Profile Control Characteristics of 1500 mm Quintic CVC Mill
Metals, 2023 Compared with cubic Continuously Variable Crown (CVC), quintic CVC presents integrated control capability of quadratic and quartic crown. In order to take full advantage of quintic CVC and have better comprehensive control of the edge wave, center wave ...
Bangshuo Wei +6 more
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Machines, 2023 Commercial vehicles generally drive at a higher speed on structured expressways, and their higher center of mass leads to a lower rollover threshold and a greater rollover risk while steering.
Zhixian Fan +3 more
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Axioms, 2023 Here, we center on the solvability of a fractional-order quadratic functional integro-differential equation with a nonlocal fractional-order integro-differential condition in the class of continuous functions.
Ahmed M. A. El-Sayed +2 more
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Quadratic Isochronous centers commute [PDF]
Applicationes Mathematicae, 1999 Summary: The author proves that every quadratic plane differential system having an isochronous center commutes with a polynomial differential system.
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Quadratic perturbations of quadratic codimension-four centers
Journal of Mathematical Analysis and Applications, 2009 We study the stratum in the set of all quadratic differential systems $\dot{x}=P_2(x,y), \dot{y}=Q_2(x,y)$ with a center, known as the codimension-four case $Q_4$. It has a center and a node and a rational first integral. The limit cycles under small quadratic perturbations in the system are determined by the zeros of the first Poincar -Pontryagin ...
Gavrilov, Lubomir, Iliev, Iliya D.
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Remote Sensing, 2021 The image of ground maneuvering targets may be defocused due to the Doppler ambiguity, high-order range migration (RM), and Doppler frequency migration (DFM) caused by the target’s complex motions in a synthetic aperture radar (SAR) system.
Mingming Tian +5 more
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N=2 SUGRA BPS Multi-center solutions, quadratic prepotentials and Freudenthal transformations [PDF]
, 2014 We present a detailed description of N=2 stationary BPS multicenter black hole solutions for quadratic prepotentials with an arbitrary number of centers and scalar fields making a systematic use of the algebraic properties of the matrix of second ...
Fernandez-Melgarejo, J. J. +1 more
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The solution of some persistent $p : -q$ resonant center problems
Electronic Journal of Qualitative Theory of Differential Equations, 2018 The notion of $p:-q$ resonant center was introduced recently and studied by several authors. In this paper we generalize the notion of a persistent center to a persistent $p:-q $ resonant center and find conditions for existence of a persistent $p:-q ...
Maja Zulj +2 more
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Vertical Jumping for Legged Robot Based on Quadratic Programming
Sensors, 2021 The highly dynamic legged jumping motion is a challenging research topic because of the lack of established control schemes that handle over-constrained control objectives well in the stance phase, which are coupled and affect each other, and control ...
Dingkui Tian +4 more
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