【摘要】 给出了微分系统无穷远点等时中心、拟等时中心的定义。通过奇点量与周期常数的计算,得到了一类三次多项式微分系统无穷远点的中心条件与拟等时中心条件,同步解决了一类有理系统的无穷远点的等时中心问题。更多还原

【Abstract】 The definitions of the isochronous center and the quasi-isochronous center at infinity for differential systems are introduced. By means of computations of singular point values and period constants, the problems of center conditions and quasi-isochronous center conditions at infinity for a class of cubic polynomial differential systems are solved. The conditions of infinity to be an isochronous center for a class of rational differential systems are also given.更多还原