A Cellular Automaton Framework for Image Processing on GPU
Claude Kauffmann, Nicolas Piché · Pattern Recognition · 2009
Definitions and termsElectrical injury, electrical shock, electrocution are often used as synonyms when trauma caused by electric current is being discussed.In this text "electrical injury" is used as the www.intechopen.comForensic Medicine -From Old Problems to New Challenges 122 term with the broadest meaning.The existing various definitions of "electrical injury" are principally similar.The Russian Bolshaya medicinskaya encyclopedia defines electrical injury as an injury caused by electric current or a result from contact with lightning.K. Duff and McCaffrey distinguish between electrical injury and lightening injury (Duff, 2001).The former they define as the sequelae due to accidental contact with man-made or generated electrical power and the later as a sequelae of naturally occurring lightening strike.According to the Merck manual electrical injury is a damage caused by generated electrical current passing through the body (Cooper, 2009). TermsInformation for the following terms is presented as a basic explanation of electricity and the effects of electrical energy (CDC, 1998). electricity (electric current) -is the directed flow of an atom's electrons (the negatively charged outer particles of an atom) through a conductor such as wire.Its main characteristics which determine the hazard effect of electricity on the human body are: voltage -the force or pressure that causes electricity to flow through a conductor, measured in volts (V).Usually household current is 110 to 220V.Anything over 500V is considered high voltage.Life threatening levels of voltage are above 50-60V.Death occurs in 25% of cases in contact with electricity of 127-380V; in 50% of contacts with 1000V; and in 100% if the voltage is 3000V.A more important characteristic is the difference of the voltage at the entrance and exit of the electric chain.A difference up to 24 V is considered acceptable according to international safety norms; power/strength -is the flow of electrons from a source of voltage through a conductor and is measured in amperes (Amps).The contact with a current with more than 60 mА per 1 sec is life threatening , and above 100 mA is usually lethal.Current up to 50 mA is accepted as less dangerous for direct current and up to 10 mА for alternating current. type of current -electrical current is categorized as direct current (DC) or alternating current (AC).Direct is the current which flows in one direction only (as in a car battery).Sources of direct current are batteries, solar cells, dynamo, etc. Alternating current (AC) is the current which flows back and forth (a cycle) through a conductor.It is more dangerous than the direct current. rate -the rate of the cycles (back and forth) of the alternating current per second is measured in Hertz.The normal rate in Europe is 50 cycles per second or 50 Hertz.In the United States it is 60 cycles per second [or 60 Hertz (Hz)].Most dangerous is electricity with a rate of 40-60 Hertz; electricity with a rate of approximately 500 kilohertz is not dangerous. resistance -is the ability to impede the flow of electricity.Most of the body's resistance is concentrated in the skin.The thicker the skin is, the greater its resistance.A thick, callused palm or sole, for example, is much more resistant to electrical current than an area of thin skin, such as an inner arm.The skin's resistance decreases when broken (for example, punctured or scraped) or when wet.If skin resistance is high, more of the damage is local, often causing only skin burns.If skin resistance is low, more of the damage affects the internal organs.Thus, the damage is mostly internal if people who are wet come in contact with electrical current, for example, when a hair dryer falls into a bathtub or people step in a puddle that is in contact with a downed electrical line www.intechopen.com