Some hearing milestones your child should reach in the first year of life: 1  Most newborn infants startle or jump to sudden loud noises. 2  By 3 months, a baby usually recognizes a parent's voice. 3  By 6 months, a baby can usually turn his or her eyes or head toward a sound.
(December 2008). Direct digital control (DDC) is the automated control of a condition or process by a digital device (computer). DDC is considered by many to be a more modern, granular and responsive update to older HVAC control systems based upon PLC technologies.
46 DDC CONTROL SYSTEM Å I.O.M. ï¬System Control Unit-Monitorï¬ Screen (see previous page for screen example) The System Control Unit-Monitor screen displays all current operating information related to the system. See thesample screen displayed on the previous page.