焦点量
焦点量的相关文献在1991年到2022年内共计70篇,主要集中在数学、物理学、自动化技术、计算机技术
等领域,其中期刊论文67篇、会议论文2篇、专利文献68162篇;相关期刊52种,包括世界华商经济年鉴·城乡建设、南阳师范学院学报、商丘师范学院学报等;
相关会议2种,包括第十届全国泛函微分方程会议、第二届全国青年常微分方程理论与应用学术会议等;焦点量的相关文献由88位作者贡献,包括杜超雄、桑波、刘一戎等。
焦点量—发文量
专利文献>
论文:68162篇
占比:99.90%
总计:68231篇
焦点量
-研究学者
- 杜超雄
- 桑波
- 刘一戎
- 黄文韬
- 万维明
- 吴兆荣
- 朱丽芹
- 丰建文
- 刘磊
- 卢景苹
- 张理
- 张齐
- 朱思铭
- 王锋
- 诸慧
- 陈士华
- 陈理
- 云连英
- 何西兵
- 刁建东
- 刘向东
- 刘灿辉
- 刘艳伟
- 刘虹
- 刘霞
- 吴新民
- 吴海涛
- 吴闽江
- 唐明田
- 唐清干
- 夏青
- 姜世民
- 孙宝法
- 宋涛
- 岳海涛
- 年亚东
- 张伯骏
- 张冬梅
- 张同华
- 张琪昌
- 张翠梅
- 彭跃辉
- 徐娜
- 徐慧栩
- 曹勃
- 朱小和
- 李威
- 李学敏
- 李宝毅
- 李星
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诸慧
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摘要:
本文考虑如下微分方程系统dx/dt=-y+x(a_(1)x+a_(2)x^(2)+·+a_(n)x^(n)),dy/dt=x+y(b_(1)y+b_(2)y^(2)+·+b_(n)y^(n))这,里ai,bi是实数,根据Poincare对称原理和结式消元,利用计算机软件Maple辅助证明,得到了当n=4,5,6,7时,原点为系统中心的充要条件。
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谢向东;
薛亚龙;
许丽莉
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摘要:
研究2n+1次多项式系统dx/dt=-y+δx+a_(2)xy+a_(5)xy^(2),dy/dt=x(1+by^(2n)),给出系统的焦点量(或奇点量)W_(0)=δ,W_(1)=a_(5).证明W_(0)W_(1)≥0时,O(0,0)外围不存在极限环;而当W_(0)W_(1)<0时,O(0,0)外围至多一个极限环.
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桑波
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摘要:
本文研究了一类Z2对称五次微分系统的中心条件和小振幅极限环分支.通过前6阶焦点量的计算,获得了原点为中心的充要条件,并证明系统从原点分支出的小振幅极限环的个数至多为6.最后通过构造后继函数,给出系统具有6个围绕原点的小振幅极限环的实例.%In this paper, the center conditions and bifurcations of small amplitude limit cycles for a class of quintic systems with Z2 symmetry are investigated. By the computations of the first six focal quantities, the necessary and sufficient conditions for the origin to be center are derived, and the maximal number of small amplitude limit cycles is proved to be 6. Finally, by constructing displacement function, a concrete example of quintic system is proved to have six small amplitude limit cycles around the origin.
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刘霞;
刘艳伟
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摘要:
根据韩茂安等所得到的计算非光滑Liénard系统的焦点量的方法,应用maple程序,给出一些较一般的非光滑Liénard系统从原点处分支出的极限环数目.%Based on the results by HAN Mao-an,et al.for computing some focus values of non-smooth Liénard systems,the number of limit cycles bifurcated from the origin of some more general non-smooth Liénard systems were given by using maple process.
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桑波
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摘要:
A full-reduction algorithm using Grobner Basis is proposed for the sequence of focal values based on the method of singular point values. As applications, the center-focus problems of two classes of cubic systems are considered and several non-trivial center conditions are obtained.%本文在奇点量方法的基础上,以Gr(o)bner基为工具,提出了焦点量序列的约化算法;作为应用,讨论了两类三次系统的中心焦点问题,给出了系统具有中心的若干非平凡条件.
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赵大虎;
卢景苹
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摘要:
讨论一类四次多项式微分系统的中心条件与极限环分支问题.通过对该实系统所对应的伴随复系统奇点量的计算,得到系统的原点成为中心的必要条件,并对它的充分性进行严格的证明.从奇点量导出焦点量,得到了原点成为8阶细焦点的条件,最后证明该系统从在原点邻域有8个小振幅极限环.这是首次得到四次系统在细焦点可分支出8个极限环.%The bifurcation of limit cycles and conditions of origin to be a center for a biquadratic polynomial system is investigated. By the computation of the singular point values for the concomitant complex system of the real system , the necessary conditions of origin of system to be a center is obtained, and the sufficiency for the conditions is strictly proven. The focal values are derived from of the singular points, and the conditions that the origin to be an 8 order weak focal is obtained. Finally, it is proved that this system has small amplitude limit cycles in the neighborhood of the origin. This is the first time that an example of a biquadratic system with eight limit cycles bifurcated from a weak focal is given.
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黄文武;
范兴宇
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摘要:
讨论一类四次多项式微分系统的中心条件与极限环分支问题.通过对该系统所对应的伴随复系统奇点量的计算及证明,得到系统的原点为中心的充要条件.从奇点量导出焦点量,得到了原点成为6阶细焦点的条件,证明了该系统可从原点领域分支出5个小振幅极限环.%In this paper, the bifurcation of limit cycles and conditions of origin to be a center for a quartic polynomial system is investigated. By the computation of the singular point values for the concomitant complex system of the real system, and prove strictly the suffciency for the conditions, we obtain the necessary conditions of origin of system to be a center. The focal values are derived from of the singular points, and the conditions is obtained that the origin to be a 6 order weak focal. Finally, 5 small amplitude limit cycles in the neighborhood of the origin in this system is proved.