| 1. | Positive semi-definite matrices are positive definite if and only if they are nonsingular .
正半定矩阵是正定的，当且仅当它们是非奇异矩阵。 |
| 2. | An advantage of the proposed method is that the generated iterative matrices are always positive definite
这种方法的一个优点是算法产生的迭代矩阵总是正定的。 |
| 3. | L ^ 2 - norm error estimates are derived under the assumption of only positive semi - definite diffusion coefficient
在扩散项系数半正定的情形得到逼近解的次优l ^ -模误差估计。 |
| 4. | A class of left and right inverse eigenvalue problems for positive definite symmetric and positive semidefinite symmetric matrices
一类对称正定及半正定的左右逆特征值问题 |
| 5. | The thesis consists of two parts . in the first part , we consider an intersection matrix that is positive semi - definite
本文由两个部分组成，第一部分考虑半正定的相交矩阵，由它我们定义了根系。 |
| 6. | An advantage of this method is that it can be applied when the covariance matrix of the invested projects is positive semi - definite
该方法的优点在于能够处理各投资项目之间的协方差矩阵为半正定的情形。 |
| 7. | Although there have been some suggestions on how to ensure the positive definiteness of the iterative matrices , they are restrictive and is not easy to be implemented
尽管已有一些关于怎样保证迭代矩阵正定的讨论，然而还没有切实可行的方案。 |
| 8. | The main difficulty for the global convergence of the structured bfgs method lies in that the matrices generated by the method may not be positive definite . as a consequent , the direction generated by the method may not be a descent direction of the objective function
建立具有全局收敛性的结构化拟newton法的一个主要困难是在于该算法产生的矩阵不一定是正定的，从而产生的搜索方向不一定是目标函数的下降方向。 |
| 9. | We fhd that the energies have the following important properties : ( 1 ) the energies are positive and monoton - ically decrease to their arnowitt - deser - misner ( adm ) masses at spatial infinity ; ( 2 ) the energies have the correct newtionial limiting , and include the binding energies from the gravitation ^ electrostatic charge and dilaton charge , respectively ; ( 3 ) martinez ' s conjecture is valid for such black holes
结果表明该能量具有如下几个重要特征： ( 1 )该能量是正定的，且随径向坐标单调递减，在无穷远处为黑洞的adm质量； ( 2 )该能量具有正确的牛顿极限，并包含有分别来自于引力、静电荷和伸缩子荷的束缚能； ( 3 ) martinez猜测对这些黑洞依旧成立。 |
