Now the ability to deliver ultrasonic energy to the lesion and trackability of catheter remain the major technical difficulties .

目前超声导管传递能量到病变 处的能力以及 导管 的 可 操作 性仍然是技术上主要的难点。

The complexities of the vehicle longitudinal dynamics result in large model uncertainties and the conventional robust or parameter adaptive control methods can hardly ensure good control performances such as control stability trackability and accuracy .

由于汽车纵向动力学系统的复杂性使得建立的模型存在较大不确定性，导致传统的 鲁棒和参数自适应控制方法很难保证良好的控制性能。

Simulation results show that this method enhances the trackability of the system has better compensation to the delay stronger adaptability to the controlled parameter and higher precision quicker speed and more excellent control quality than traditional methods .

仿真结果表明，此方法增强了系统的 跟踪 性，对纯滞后具有较好的补偿作用，对被控参数具有较强的适应能力，比传统的控制方法精度高、速度快、控制质量优良。

Computer simulations show that the signal trackability of this algorithm approximates very well that of the minimum variance distortionless response ( MVDR ) algorithm .

仿真实验表明，该算法的信号 跟踪 能力与最小方差无畸变响应（MVDR）算法的 跟踪 能力十分接近。

The trackability limitation of current gradient algorithm is discussed . A new algorithm named variable parameter gradient estimation algorithm with local polynomial approximation is proposed .

本文分析了梯度 辨识算法 跟踪 时 变 系统的缺点，提出了一种新的基于局部多项式逼近的变参数梯度估计算法。