Factors related to workers and tasks have a combined effect on system performance. Management tends to make effective decisions by understanding the dynamics of the workers' performance over time, affected by their time-varying learning, fatigue, and stress levels. Such managerial decisions could improve system productivity and ensure workforce safety. Despite the importance of the problem, the literature did not focus on the performance modelling or task planning framework that includes all the mentioned factors, i.e., learning, fatigue, and stress. This dissertation includes three main contributions with different performance modelling and task allocation/scheduling planning that help managers plan mission operations, characterized as uncertain, dynamic, and time-sensitive. The first contribution (Chapter 3) is a mathematical model that modifies a popular learning curve model from the literature by making its learning exponent dependent on the fatigue level. The results of applying this model to a data set (vs. the other available ones in the literature,) showed an outperformance in terms of efficiency and balance criteria.