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.
Defense Mechanism A defense mechanism is a way for the mind to protect us from being consciously aware of thoughts or feelings that are too difficult to tolerate. Since the thought or feeling is too difficult to tolerate the defense mechanism only allows the unconscious thought or feeling to be expressed indirectly in some type of disguised form.