S Your new gas furnace may have been installed in one of two. ways, as a direct-vent (2-pipe-Fig. 2) application or as a. non-direct vent (1-pipe-Fig. 3) application. S In a direct-vent (2-pipe) application,your furnace uses air. from outside the home for combustion and ventsflue gas to the. outdoors.
For the biological concept, see Anti-predator adaptation. A defence mechanism is an unconscious psychological mechanism that reduces anxiety arising from unacceptable or potentially harmful stimuli. Sigmund Freud was one of the first proponents of this construct.
The Department of the Navy's Theater Ballistic Missile Defense (TBMD) programs will provide layered defense against a wide range of theater ballistic missiles, encompassing area defense to protect joint forces in littoral areas and coastal airfields, and a sea-based theater-wide capability to protect vital assets throughout entire regions.