- Ethernet (this name comes from the physical concept of ether) is a frame-based computer networking technology for local area networks (LANs). It defines wiring and signaling for the physical layer, an. Used . d frame formats and protocols for the media access control (MAC)/data link layer of the OSI model. Ethernet is mostly standardized as IEEEs 802.3. It has become the most widespread LAN techno. Used . logy in use during the 1990s to the present, and has largely replaced all other LAN standards such as token ring, FDDI, and ARCNET. ...Arc Lamp
- An arc lamp is a device that produces light by the sparking (or arcing, from voltaic arc or electric arc) of a high current between two carbon rod electrodes. The rods are touched and then slowly draw. Used . n apart; as the rods separate the current is "struck" and arcs across the gap in a bright, ionized path. The arc produces a temperature of several thousand degrees, and the tips of the carbon. Used . rods are heated to incandescence, creating light. The rods are slowly vaporized during the process and need to be regularly adjusted to maintain the arc. The concept was first demonstrated by Sir Humphry Davy...Kelvin
- The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. It is defined by two facts: zero kelvins is absolute zero (when molecular motion stops), and one kelvin is . Used . the fraction 1/273.16 of the thermodynamic temperature of the triple point of water. The Celsius temperature scale is now defined in terms of the kelvin, with 0 °C corresponding to 273.15 kel. Used . vins, approximately the freezing point of water under ordinary conditions.
The kelvin is named after the British physicist and engineer William Thomson, 1st Baron Kelvin; his barony was in turn na...Fresnel
- Fresnels are typically 8-, 6- or 4-inch, referring to the diameter of the lens. This light is named after Augustin-Jean Fresnel who invented the distinctive Fresnel lens which has a 'stepped' appearan. Used . ce instead of the 'full' or 'smooth' appearance of other lenses. The stepped nature of the lens causes a corresponding pattern of circles of light, so Fresnel lenses are usually 'stippled' on. Used . the flat side. This pattern of small bumps helps to break up the light passing into the lens to smooth out its eventual pattern.
Fresnels use a spherical reflector, with the filament of the bulb ...Subtractive Color
- Subtractive color explains the theory of mixing paints, dyes, inks, and natural colorants to create colors which absorb some wavelengths of light and reflect others. The color that an object appears t. Used . o have is based on what parts of the electromagnetic spectrum are reflected by it, or conversely by what parts of the spectrum are not absorbed.
Anything that is not additive col. Used . or is subtractive color. No other color mixing systems are known, except the imperfect system resulting from mixing real pigments, something that is very confusing nowadays.
Color is not an absolu...