time-variance meaning in English

时间变异

The wastewater treatment system is one dynamic system of indeterminacy , time - variance , nonlinearity and posteriority . so it is difficult to create a precise mathematical model
城镇污水处理系统是一个具有不确定性、时变性、非线性、滞后性的动态系统,难于建立起精确的数学模型。
The results show that although dbm method can fit the systems with high precision , avoid over - fitting and accurately reflect the time - variance and state - dependency in the systems , it may also reduce the efficiency of the whole method due to the exponentially increasing calculating numbers with the increase of the number of the states . and genetic algorithm is introduced to improve the search efficiency
接着利用dbm方法和其他非线性辨识算法分别对时变参数方程、 lorenz方程和杜芬方程进行分析和比较,发现尽管方法本身具有拟合精度高,不存在过拟合现象,可以较精确的反应参数对于状态或者时间的依存关系等特点,但是sdp方法在分析复杂问题时存在搜索效率低,计算时间长的缺点。