In production environments, such as Flexible Manufacturing Systems (FMSs), the schedule can be disturbed by the occurrence of unplanned events. Machines stop for major failures, maintenance, tool changes due to wear, or tool reassignments. The rescheduling process, however, can be costly. In this study, a dynamic measure of flexibility which helps to determine an appropriate time for rescheduling an FMS has been defined and investigated. Flexibility is defined as a function of Capability and Capacity. Accordingly, two metrics have been developed to monitor the capability and capacity efficiency of each machine in the system for responding to the dynamic system status. The value of each metric falls between 0 and 1 at all times. Higher values in the capability metric mean better machine selection and part distribution strategies among the machines. Higher values for the capacity metric mean higher machine utilization in the production plan. Based on the interaction between the metrics and their respective behavior in the system, four states have been identified and characterized. Simulations of various scenarios can be used to demonstrate the use of these metrics for monitoring FMS operations and determining appropriate times for rescheduling and tool reassignment.

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The rapid advance of technology has presented authorities with many new tools that they can use to monitor and control roadways for their safe, efficient, and convenient use by motorists, working toward an intelligent transportation system that adapts to dynamic situations that best serve motorists. Recent natural and human-caused disasters have demonstrated that there are significant challenges yet to be overcome by the advancing technology of transportation systems. A significant problem is a lack of clear, efficient communication during emergencies. The public requires timely information and guidance during and after a catastrophic event. This research investigated the feasibility of enhancing transportation system preparedness by creating messages to aid motorists during natural or human-caused disasters by supplementing the existing message display libraries for variable message signs (VMSs) and dynamic message signs (DMSs). This investigation considered the current transportation emergency communication environment and attempts to enhance communication and preparedness by improving the design and display of messages on VMSs and DMSs. The study examined 465 Rhode Island drivers by using a computer survey and 157 Rhode Island drivers by using driving simulation to research important factors in the design and deployment of message displays. The results indicated that the supplementation of communication through the use of VMSs and DMSs is a viable alternative and that there are design factors that can be used to help develop new and improve existing messages through further testing and implementation.

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