本文对现有的变分不等式问题的二次外梯度投影算法进行分析，并对可行域为球的二次外梯度投影算法的计算过程进行简化。
This paper makes an analysis of this quadratic outer gradient project algorithms and simplifies the process of the computation of projection needed in this method for the case of domain being a ball.
如果天文学家能够观测到十亿光年外的螺旋星云的金属丰度梯度，我们就可以知道亿万年之前的梯度有多大，因此也就可以知道它是如何随时间变化的。
If astronomers could observe metallicity gradients in spiral galaxies billions of light-years away, we could see how steep the gradients were billions of years ago and thus how they change over time.
为了在单边核磁共振仪器外产生梯度恒定的磁场，提出利用基于拓扑优化和有限元法的优化设计方法。
To obtain a constant gradient magnetic field outside unilateral nuclear magnetic resonance (NMR), optimal design method based on finite element method (FEM) and topology optimization is proposed.
应用推荐