A power control system for saving power by powering on enough application servers to satisfy the current load workload as well as any required reserve capacity based on administrative settings is disclosed. This control is made possible by two new terms added to standard flow equations: a driving force term that causes the fluid to carry the smoke towards a particular target, and a smoke gathering term that prevents the smoke from diffusing too much. Embodiments are configured to allow complex data records having a plurality of related fields, and to allow management and exchange of information at both the data field level and data record level. Each file is sent to a different and typically geographically distinct data storage location. The cabs are mounted on two opposing vertical guide rails, and each guide rail is mounted at the center of one side of the elevator shaft.