| 700 / | HD | DATA PROCESSING: GENERIC CONTROL SYSTEMS OR SPECIFIC APPLICATIONS |
| 90 | DD | SPECIFIC APPLICATION, APPARATUS OR PROCESS {16} |
| 275 | DD | .~ Mechanical control system {5} |
| 282 | DD | .~.~ Flow control (e.g., valve or pump control) {2} |
| 285 | | .~.~.~ Fluid mixing |