Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value

[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment.

停车场视频监视系统中的阴影检测方法

停车场视频监视系统能够同时完成对停车场车位空满状态的判断和对是否存在压线违规停车状态的判断。车辆的阴影会直接影响系统对车位空满和车辆违章停放的正确判别。为此,本文采用一种基于灰度比值统计与位置聚类的阴影检测方法,完成对阴影区域的检测。首先,采用正态分布曲线来拟合灰度比值分布曲线中阴影区域的分布,根据正态分布给出的置信区间,检测出阴影的候补区域,之后,再利用位置聚类的方法,滤除误检测为阴影的目标点。实验结果表明,本文所提出的方法,对各类光照环境具有较强的适用性。