Abstract: Buffer management is the core of critical chain project management. Buffer monitoring can prevent buffers from being wasted during the project execution stage and ensure the project's duration. Effective monitoring methods are beneficial to improve the overall performance of the project. Cost and duration are two key factors in project management, and the sensitivity of activities to costs and duration is different. If a unified buffer monitoring model is adopted for all activities, it may lead to waste of costs and duration. In order to overcome the shortcomings of the unified buffer monitoring method, on the basis of ensuring the project duration, the impact of cost factors on the project is considered, and a dynamic buffer monitoring model is proposed based on the different cost and duration sensitivity. The model considers process heterogeneity to divide activities into cost-sensitive activities and duration-sensitive activities, allocates buffer monitoring assignments based on the overall perceived utility of the activity, and sets different monitoring reference points and corrective measures for different types of activities. Among them, the cost-sensitive activity sets a lower buffer monitoring reference point, and the duration-sensitive activity sets a higher buffer monitoring reference point. The simulation results show that compared with the unified monitoring mode, differential monitoring is conducive to double optimization of project duration and cost, which verifies the effectiveness of the method in this paper.

Key words: critical chain project management; integrated perception utility; time sensitive activity; cost sensitive activity; differential buffer monitoring