Abstract: Qualitative process trend representation is a useful approach to model temporal evolution of sensor data by computer，Qualitative Trend Analysis（QTA） has been widely used for process monitoring，data compression and Fault Detection and Diagnosis（FDD）.The first section summarizes the background and up-to-date development of Qualitative Trend Analysis（QTA）;Then effective methodologies in trend extraction and some major problems in trend identification of Qualitative Trend Analysis（QTA） are proposed.The results issued this method can capture process trend from the data effectively and rapidly.

Key words: Qualitative Trend Analysis（QTA）, process monitoring, trend extraction, data analysis, trend identification

摘要： 为了对传感器数据的瞬态演化用计算机进行建模，提出了定性趋势分析（Qualitative Trend Analysis），这种定性的过程趋势描述是一种很有用的方法，已被广泛地用于过程状态监测、数据压缩、故障检测和诊断。首先概述国外QTA的产生背景和发展情况;其次提出有效的QTA趋势提取策略和趋势识别的若干重要问题。结果表明，该方法能够有效和快速地从数据中获取过程趋势。

关键词: 定性趋势分析（QTA）, 过程监测, 趋势提取, 数据分析, 趋势识别