| 摘要 |
<p>A four channel gas delivery system. The system comprises an inlet channel; four outlet channels; four control valves, each valve being arranged so as to control the flow from the inlet channel through a corresponding one of the outlet channels; and a flow ratio control system. The flow ratio control system includes two dual antisymmetric optimal (DAO) control modules. The DAO control modules are configured and arranged so as to control the respective control valves so as to control the relative ratios of flow from the inlet channel through the four outlet channels. The flow ratio control system also includes a virtual DAO control module configured and arranged so as to control the ratio of flow between the two DAO control modules.</p> |
