covariance model的用法和样例：
例句
- The correctness of the similar single-difference model and the validity of the method of identifying outliers are verified with the test data.
利用试验数据对似单差模型的正确性及粗差识别方法的有效性进行了检验。 - The generalized model for kinematic adjustment,which includes various static and linear kinematic adjustment models,is introduced in the paper.
建立了包括各种静态平差模型和线性动态平差模型的动态平差概括模型，推导了其主要求解公式。
