A new approach to model and control an unknown system using subjective uncertain rules is proposed. This method is established by combining the grey system theory and the qualitative simulation method. The proposed approach mainly contains three steps. In the first step, subjective uncertain rules are accumulated gradually during cognizing the system; the mapping relations between the system inputs and outputs are built and represented using the grey qualitative matrix in the second step; in the third step,the generalized whitening function is defined to realize the transformation between qualitative and quantitative information. Besides the theoretical results, two sets of simulations based on a water level control system are conducted comparatively to demonstrate the effectiveness of the proposed method. The water level expectation is set to be constant in the first set, while it changes in the second set. The simulation results show that the proposed method tracks the water level expectation well. By combining the proposed method with proportional-integral-derivative(PID) or fuzzy logic controller(FLC), it can be concluded that the system can reach the stable state more quickly and the overshoot can also be reduced compared to using PID or FLC alone.
针对当前常见的显著性方法检测得到的显著性区域边界稀疏不明确、内部不均匀致密等问题,提出了一种基于条件随机场(Condition random field,CRF)和图像分割的显著性检测方法.该方法综合利用边界信息、局部信息以及全局信息,从图像中提取出多种显著性特征;在条件随机场框架下融合这些特征,通过显著性区域与背景区域的区域标注实现显著性区域的粗糙检测;结合区域标注结果和交互式图像分割方法实现显著性区域的精确检测.实验结果表明本文提出的方法能够清晰而准确地提取出图像中的显著性区域,有效提高显著性检测精度.
