In this thesis, we present a detailed analysis of hybrid point-to-multipoint free space optical (FSO)/radio frequency (RF) wireless system. Hybrid FSO/RF sys- tems have emerged as a promising solution for high data rate wireless transmission. FSO technology can be used effectively in multiuser scenarios to support Point-to- Multi-Point (P2MP) networks. In this P2MP network, FSO links are used for data transmission from a central location to multiple users. When more than one FSO link fail, the central node uses a common backup RF link to transmit a frame to a remote node using an equal priority protocol. An equal priority protocol means that the remote nodes have the same priorities in being assigned the RF link. We assume two traffic classes, a high-priority and low-priority classes. The base station reserves two transmit buffers of each user for the downlink transmission. Considering the downlink traffic from the base station to a tagged remote node, we study several performance metrics. We develop a cross-layer Markov chain model to study the throughput from central node to a remote node as well as the performance of the resulting system. / Graduate

Emergency surgeries are serviced by three main forms of capacity: dedicated operating room time reserved for emergency surgeries, alternative (on call) capacity, and lastly, canceling of elective surgeries. The objective of this research is to model capacity implications of meeting wait time targets for multiple priority levels in the context of emergency surgeries. Initial attempts to solve the capacity evaluation problem were made using a non-linear optimisation model, however, this model was intractable. A simulation model was then used to examine the trade-off between additional dedicated operating room capacity (and consequent idle capacity) versus increased re-scheduling of elective surgeries while keeping reserved time for emergency surgeries low. Considered performance measures include utilization of operating room time, elective re-scheduling, and wait times by priority class. Finally, the instantaneous utilization of different types of downstream beds is determined to aid in capacity planning. The greatest number of patients seen within their respective wait time targets is achieved by a combination of additional on call capacity and a variation of the rule allowing low priority patients to utilize on call capacity. This also maintains lower cancelations of elective surgeries than the current situation. Although simulation does not provide an optimum solution it enables a comparison of different scenarios. This simulation model can determine appropriate capacity levels for servicing emergency patients of different priorities with different wait time targets.

Emergency surgeries are serviced by three main forms of capacity: dedicated operating room time reserved for emergency surgeries, alternative (on call) capacity, and lastly, canceling of elective surgeries. The objective of this research is to model capacity implications of meeting wait time targets for multiple priority levels in the context of emergency surgeries. Initial attempts to solve the capacity evaluation problem were made using a non-linear optimisation model, however, this model was intractable. A simulation model was then used to examine the trade-off between additional dedicated operating room capacity (and consequent idle capacity) versus increased re-scheduling of elective surgeries while keeping reserved time for emergency surgeries low. Considered performance measures include utilization of operating room time, elective re-scheduling, and wait times by priority class. Finally, the instantaneous utilization of different types of downstream beds is determined to aid in capacity planning. The greatest number of patients seen within their respective wait time targets is achieved by a combination of additional on call capacity and a variation of the rule allowing low priority patients to utilize on call capacity. This also maintains lower cancelations of elective surgeries than the current situation. Although simulation does not provide an optimum solution it enables a comparison of different scenarios. This simulation model can determine appropriate capacity levels for servicing emergency patients of different priorities with different wait time targets.

Emergency surgeries are serviced by three main forms of capacity: dedicated operating room time reserved for emergency surgeries, alternative (on call) capacity, and lastly, canceling of elective surgeries. The objective of this research is to model capacity implications of meeting wait time targets for multiple priority levels in the context of emergency surgeries. Initial attempts to solve the capacity evaluation problem were made using a non-linear optimisation model, however, this model was intractable. A simulation model was then used to examine the trade-off between additional dedicated operating room capacity (and consequent idle capacity) versus increased re-scheduling of elective surgeries while keeping reserved time for emergency surgeries low. Considered performance measures include utilization of operating room time, elective re-scheduling, and wait times by priority class. Finally, the instantaneous utilization of different types of downstream beds is determined to aid in capacity planning. The greatest number of patients seen within their respective wait time targets is achieved by a combination of additional on call capacity and a variation of the rule allowing low priority patients to utilize on call capacity. This also maintains lower cancelations of elective surgeries than the current situation. Although simulation does not provide an optimum solution it enables a comparison of different scenarios. This simulation model can determine appropriate capacity levels for servicing emergency patients of different priorities with different wait time targets.