The researchers used 'diffusion tensor' magnetic resonance imaging (MRI), which depicts the diffusion, or displacement, of water molecules through tissue.
研究人员使用“扩张量”核磁共振技术，即描述组织中的水分子的扩散或者置换程度。
2
Normal modes in the pole and important characteristic parameters such as resonance frequency and position of the displacement node are obtained using the finite element method.
并应用有限元法对变幅杆进行了模态分析，得到了共振频率和位移节点等重要参数。
3
Then theoretical resonance length, small end diameter, displacement node, magnification factor, shape factor and other parameters of the amplitude amplifier pole could be determined.