دانلود رایگان مقاله انگلیسی اعتبار تجربی از عملکرد محدودیت تحمل کنترل پروژه - الزویر 2018

ABSTRACT

The goal of project control is monitoring the project progress during project execution to detect potential problems and taking corrective actions when necessary. Tolerance limits are a tool to assess whether the project progress is acceptable or not, and generate warnings signals that act as triggers for corrective action to the project manager. In this paper, three distinct types of tolerance limits that have been proposed in literature are validated on a large and diverse set of real-life projects mainly situated in the construction sector. Moreover, a novel approach to construct tolerance limits that integrate the project risk information into the monitoring process is introduced. The results of the empirical experiment have shown that integrating project-specific information into the construction of the tolerance limits results in a higher efficiency of the monitoring process. More specifically, while including cost information increases the efficiency only marginally, incorporating the available resource information substantially improves the efficiency of the monitoring process. Furthermore, when projects are not restricted by scarce resources, the efficiency can be enhanced by integrating the available project risk information.

Conclusion

In this paper, three types of analytical tolerance limits proposed in literature have been empirically validated on a large set of real-life project data, mainly situated in the construction sector. Further, a novel approach to construct analytical tolerance limits that incorporate activity risk information are introduced and empirically validated. Three experiments have been conducted in which the cost, resource and risk limits have been compared to the linear benchmark limits. First, the cost limits established in [5] are evaluated on a set of 93 reallife projects. These cost limits adopt a cost perspective by assigning a portion of the project buffer to each project phase proportionally with the planned cost of that phase. The performance of the cost limits is compared to the linear limits for 48 regular projects and 45 irregular projects. Second, the resource limits have been implemented for the 21 projects in the data set that contained the required information. These limits consider a resource perspective for two reasons. Firstly, expressing the planned and earned progress in terms of value is, as demonstrated in the first experiment, not necessarily accurate for real-life projects. Therefore, [6] propose to express and monitor the planned and earned progress in terms of work content units instead of costs. Secondly, when renewable resources are limitedly available, resource conflicts are an important cause of project delays. Therefore, the shiftability of each project phase, defined as the ability to shift activities to the right without endangering the project makespan, is considered in the construction of the resource limits. In the third experiment, the risk limits have been evaluated on a set of 32 projects that provided the required activity risk information. These limits have been introduced to improve the performance of analytical tolerance limits by considering the activity duration variability.