The ramp metering rate is determined by the PID controller whose parameters are tuned by fuzzy logic according to the density tracking error and errorvariation.
斜坡根据密度跟踪误差和误差变化情况，通过模糊逻辑对控制器参数进行调整，确定了测量速度。
2
There is no significant differences in systematic and random set-up errors after shrinking field, except that the random set-up errorvariation is greater in the left-right direction.
缩野前后除左右方向上随机误差有显著差异外，其他各方向系统误差和随机误差没有显著差别。
3
If this compass variation or error is not compensated for, a navigator could find himself far off course and in deep trouble.