Friday, February 1, 2008
Climate Controlled Clothing.
The global warming controversy is a dispute regarding the nature and consequences of global warming. The disputed issues include the causes of increased global average air temperature, especially since the mid-20th century; whether this warming trend is unprecedented or within normal climatic variations; whether the increase is real or partially an artifact of poor measurements. Additional disputes concern estimates of climate sensitivity; predictions of additional warming; what the consequences are; and what action should be taken (if any). Individuals, corporations, and political organizations are involved, so the debate is vigorous in the popular media and on a policy level.
V.H.F. : Very high frequency (VHF) is the radio frequency range from 30 MHz to 300 MHz. It is also known as the meter band or meter wave as the wavelengths range from ten to one meters. Frequencies immediately below VHF are denoted HF, and the next higher frequencies are known as Ultra high frequency (UHF).
U.H.F. : Ultra high frequency (UHF) designates a range (band) of electromagnetic waves whose frequency is between 300 MHz and 3 GHz (3,000 MHz). Also known as the decimeter band or decimeter wave as the wavelengths range from ten to one decimeters. Radio waves whose frequency is above the UHF band fall into the SHF (Super high frequency) and EHF (Extremely high frequency) bands; all of which fall into the Microwave frequency range. Lower frequency signals fall into the VHF or lower bands. See electromagnetic spectrum for a full listing of frequency bands.