中文摘要：

将多目标智能优化算法与梯度算法的进化策略有机结合，即对每一种群用梯度算法求解其下一代新群体，并采用实数运算，构造一种混合多目标梯度算法。利用测试函数分析算法的优劣，并将其应用于IMRT逆向计划过程。目标函数中的PTV和NT是基于平均计量分布，通过水模中的测试算例，得出强度分布。结果表明，该混合多目标梯度算法可节省大量计算时间且具有较高的计算精度，故能够满足实际应用的要求。

英文摘要：

The intelligent optimization of a multi-objective evolutionary algorithm is combined with a gradient algorithm. The hybrid multi-objective gradient algorithm is framed by the real number. Test functions are used to analyze the efficiency of the algorithm. In the simulation case of the water phantom, the algorithm is applied to an inverse planning process of intensity modulated radiation treatment （IMRT）. The objective functions of planning target volume （PTV） and normal tissue （NT） are based on the average dose distribution. The obtained intensity profile shows that the hybrid multi-objective gradient algorithm saves the computational time and has good accuracy, thus meeting the requirements of practical applications.