| 1. | The center - focus decision for a class of poincar equation
方程的中心焦点判定 |
| 2. | On the decision of the center or focus for a class of planar quintic system
一类平面五次系统的中心焦点判定 |
| 3. | Study of center focus decision problem for a type of polynomial system
一类多项式系统中心焦点判定问题的研究 |
| 4. | On the decision problem of the center or focus for a class of 5th differential system
一类五次系统的中心焦点判定 |
| 5. | The sufficient and necessary conditions of the centre - focus criterion for a class of cubic differential system are given
摘要给出了一类三次多项式微分系统中心焦点判定的充分必要条件。 |
| 6. | This thesis is devoted to center - focus determination and bifurcation of limit cycles from the equator in planar polynomial differential systems . it consists of seven chapters
本论文研究平面多项式微分系统的中心焦点判定与赤道极限环分支，由七章组成。 |
| 7. | From chapter 3 to chapter 6 , the center - focus determination and bifurcation of the equator are studied for real planar odd polynomial differential systems
在第三章至第六章，我们研究实平面奇数次多项式微分系统无穷远点(赤道)的中心焦点判定与赤道极限环分支。 |
| 8. | In chapter 1 , the background and present conditions are introduced and summarized for the study of center - focus determination and bifurcation of limit cycles of the equator for planar polynomial differential systems
在第一章，我们对平面多项式微分系统的中心焦点判定与赤道极限环分支问题研究的历史背景与现状进行了全面综述。 |
| 9. | In chapter 2 , by studying the computation of the quantities of singular point of the original of the following complex autonomous polynomial differential system two linear recursion formulas for the computation of quantities of singular point of system ( 1 ) are obtained . applicable formulas are presented unitedly for the computation of focus quantities and saddle quantities , which play an important role in center - focus determination and bifurcation of limit cycles in real planar polynomial differential systems
在第二章，我们研究平面多项式复自治微分系统原点的奇点量计算，得到了奇点量计算的线性代数递推公式，统一地给出了在实平面多项式微分系统的中心焦点判定与极限环分支中有着极为重要意义的焦点量与鞍点量的易于应用的计算公式。 |
| 10. | Current , it is a focus with big cross , arrive for ray north with the road in china north fountain , to on the west with zhongshan the fountain that the road is end points of the big cross that ray is comprised to daximen on the west and regards a center as the focus , north on the west is mixed on the west the daximen of end points , regard oneself as the center of area with the roundabout of respective traffic thoroughfare respectively , formed the commercial area with 3 relatively flourishing diminutive , in local citizen memory acknowledge is spent taller
目前，以大十字为焦点，向北以中华中路为射线北到喷水池，向西以中山西路为射线西到大西门组成而作为中心焦点的大十字、北端点的喷水池和西端点的大西门，分别以各自交通要道的交叉路口作为自身区域的中心，形成了三个小型的较为繁华的商业区域，在当地市民心目中认知度较高。 |
