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.
DDT, is a colorless chemical pesticide, [dichlorodiphenyltrichloroethane], used even today to eradicate disease-carrying and crop-eating insects. It was first isolated in Germany in 1874, but not until 1939 did the Swiss Nobel Prize-winning chemist Paul Mueller mÃ¼ller recognize it as a potent nerve poison to. insects