Quantifying the Main Battle Tank's architectural trade space using Bayesian Belief Network

Abstract

The design and development of a Main Battle Tank can be characterized as a technically challenging and organizationally complex project. These projects are driven not only by the essential engineering and logistic tasks; as the frequency of technological innovation increases system architects are motivated to apply an effective method to assess the risks and benefits of adopting technological alternatives. This thesis applies Bayesian Belief Network as a quantitative modeling and metrics calculation framework in establishing the preference order of possible architectural choices during the development of a Main Battle Tank. A framework of metrics was developed for the architect to communicate objectively with stakeholders and respond to challenges raised. These inputs were then encoded as variables in a global Bayesian Belief Network. Using a change propagation algorithm any changes in the probabilities of individual variables would trigger changes throughout the entire network and can be used as informing messages to the stakeholders to reflect the consequences of these changes. Two Bayesian Belief Networks were developed and tested to understand the effectiveness and sensitivities to the variables. The successful development of the Bayesian Belief Network offers technical and organizational benefits to the system architect. From the technical viewpoint, the model benefits include performing system tradeoff studies, iterating the design to incorporate feedback quickly, analyzing the sensitivity and impact of each design change to the overall system, and identifying critical areas to allocate resources. From an organizational process perspective, it enables speedier knowledge transfer in the project, and enables the engineers

(cont.) to be knowledgeable about how their localized change could affect other sub-systems.