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Color Code
A color code is a system for encoding and representing non-color information with colors to facilitate communication. This information tends to be categorical (representing unordered/qualitative categories) though may also be sequential (representing an ordered/quantitative variable). History The earliest examples of color codes in use are for long-distance communication by use of flags, as in semaphore communication. The United Kingdom adopted a color code scheme for such communication wherein red signified danger and white signified safety, with other colors having similar assignments of meaning. As chemistry and other technologies advanced, it became expedient to use coloration as a signal for telling apart things that would otherwise be confusingly similar, such as wiring in electrical and electronic devices, and pharmaceutical pills. Encoded Variable A color code encodes a variable, which may have different representations, where the color code type should match th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
25 Pair Color Code Chart
5 (five) is a number, numeral (linguistics), numeral and numerical digit, digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. Humans, and many other animals, have 5 Digit (anatomy), digits on their Limb (anatomy), limbs. Mathematics 5 is a Fermat prime, a Mersenne prime exponent, as well as a Fibonacci number. 5 is the first congruent number, as well as the length of the hypotenuse of the smallest integer-sided right triangle, making part of the smallest Pythagorean triple (3, 4, 5). 5 is the first safe prime and the first good prime. 11 forms the first pair of sexy primes with 5. 5 is the second Fermat number, Fermat prime, of a total of five known Fermat primes. 5 is also the first of three known Wilson primes (5, 13, 563). Geometry A shape with five sides is called a pentagon. The pentagon is the first regular polygon that does not Tessellation, tile the Plane (geometry), plane with copies of itself. It is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminosity
Luminosity is an absolute measure of radiated electromagnetic radiation, electromagnetic energy per unit time, and is synonymous with the radiant power emitted by a light-emitting object. In astronomy, luminosity is the total amount of electromagnetic energy emitted per unit of time by a star, galaxy, or other astronomical object, astronomical objects. In SI units, luminosity is measured in joules per second, or watts. In astronomy, values for luminosity are often given in the terms of the Solar luminosity, luminosity of the Sun, ''L''⊙. Luminosity can also be given in terms of the astronomical Magnitude (astronomy), magnitude system: the Absolute magnitude#Bolometric magnitude, absolute bolometric magnitude (''M''bol) of an object is a logarithmic measure of its total energy emission rate, while absolute magnitude is a logarithmic measure of the luminosity within some specific wavelength range or Passband, filter band. In contrast, the term ''brightness'' in astronomy is gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PC System Design Guide
The PC System Design Guide (also known as the PC-97, PC-98, PC-99, or PC 2001 specification) is a series of hardware design requirements and recommendations for IBM PC compatible personal computers, compiled by Microsoft and Intel Corporation during 1997–2001. They were aimed at helping manufacturers provide hardware that made the best use of the capabilities of the Microsoft Windows operating system, and to simplify setup and use of such computers. Every part of a standard computer and the most common kinds of peripheral devices are defined with specific requirements. Systems and devices that meet the specification should be automatically recognized and configured by the operating system. Versions Four versions of the PC System Design Guide were released. In PC-97, a distinction was made between the requirements of a ''Basic PC'', a ''Workstation PC'' and an ''Entertainment PC''. In PC-98, the ''Mobile PC'' was added as a category. In PC 2001, the ''Entertainment PC'' was dropp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jump Start (vehicle)
A jump start, also called a boost, is a procedure of starting a motor vehicle (most commonly cars or trucks) that has a discharged battery. A temporary connection is made to the battery of another vehicle, or to some other external power source. The external supply of electricity recharges the disabled vehicle's battery and provides some of the power needed to crank the engine. Once the vehicle has been started, its normal charging system will recharge, so the auxiliary source can be removed. If the vehicle charging system is functional, leaving the engine running will restore the charge of the battery. Motorists may carry jumper cables and other equipment in case of accidental discharge of the vehicle battery (for example, by headlights, interior lights or ignition switch left on while the engine is not running). Safe procedures for connecting and disconnecting cables are given in the vehicle manual. Jumper cables Jumper cables, also known as booster cables or jump leads, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethernet Physical Layer
The physical-layer specifications of the Ethernet family of computer network standards are published by the Institute of Electrical and Electronics Engineers (IEEE), which defines the electrical or optical properties and the transfer speed of the physical connection between a device and the network or between network devices. It is complemented by the MAC layer and the logical link layer. An implementation of a specific physical layer is commonly referred to as PHY. The Ethernet physical layer has evolved over its existence starting in 1980 and encompasses multiple physical media interfaces and several orders of magnitude of speed from to . The physical medium ranges from bulky coaxial cable to twisted pair and optical fiber with a standardized reach of up to 80 km. In general, network protocol stack software will work similarly on all physical layers. Many Ethernet adapters and switch ports support multiple speeds by using autonegotiation Autonegotiation is a si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Color Code
An electronic color code or electronic colour code (see spelling differences) is used to indicate the values or ratings of electronic components, usually for resistors, but also for capacitors, inductors, diodes and others. A separate code, the 25-pair color code, is used to identify wires in some telecommunications cables. Different codes are used for wire leads on devices such as transformers or in building wiring. History Before industry standards were established, each manufacturer used its own unique system for color coding or marking their components. In the 1920s, the RMA resistor color code was developed by the Radio Manufacturers Association (RMA) as a fixed resistor coloring code marking. In 1930, the first radios with RMA color-coded resistors were built. Over many decades, as the organization name changed (RMA, RTMA, RETMA, EIA) so was the name of the code. Though known most recently as EIA color code, the four name variations are found in books, magazines, cata ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiber-optic Cable
A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable is used. Different types of cable are used for fiber-optic communication in different applications, for example long-distance telecommunication or providing a high-speed data connection between different parts of a building. Design Optical fiber consists of a core and a cladding layer, selected for total internal reflection due to the difference in the refractive index between the two. In practical fibers, the cladding is usually coated with a layer of acrylate polymer or polyimide. This coating protects the fiber from damage but does not contribute to its optical waveguide properties. Individual coated fibers (or fibers formed into ribbons or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio And Video Interfaces And Connectors
Audio connectors and video connectors are electrical or optical connectors for carrying audio or video signals. Audio interfaces or video interfaces define physical parameters and interpretation of signals. Some connectors and interfaces carry either audio only or video only, whereas others carry both, audio and video. For digital audio and digital video, this can be thought of as defining the physical layer, data link layer, and most or all of the application layer. For analog audio and analog video these functions are all represented in a single signal specification like NTSC or the direct speaker-driving signal of analog audio. Physical characteristics of the electrical or optical equipment include the types and numbers of wires required, voltages, frequencies, optical intensity, and the physical design of the connectors. Any data link layer details define how application data is encapsulated (for example for synchronization or error-correction). Application layer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ANSI Z535
ANSI Z535 are American-developed Technical standard, standards designed to improve the identification of potential hazards to workers and/or property. The identifications are called Hazardous Communication (HazCom). ANSI Z535 sets the design and application standards for all HazCom used across North America and globally, in most industrialized nations. ANSI Z535 standards integrate with international International Standards Organization, ISO ISO 3864, 3864 standards, ensuring the widest compliance, globally, with export/import laws. ANSI Z535 standardized HazCom may appear on workplace walls, industrial machines, at industrial access points, on electrical controls, inside product user guides, and on export documentation. Sub-Standards ANSI Z535 standards are described in the following individual instruction books for six specific HazCom categories: * ANSI Z535.1 American National Standard for Safety Colors ** Red – power lines and conduits ** Orange – telecom lines ** Ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
25-pair Color Code
The 25-pair color code, originally known as even-count color code, is a color code used to identify individual conductors in twisted-pair wiring for telecommunications. Color coding With the development of new generations of telecommunication cables with polyethylene-insulated conductors (''PIC'') by Bell Laboratories for the Bell System in the 1950s, new methods were developed to mark each individual conductor in cables. Each wire is identified by the combination of two colors, one of which is the major color, and the second the minor color. Major and minor colors are chosen from two different groups of five, resulting in 25 color combinations. The color combinations are applied to the insulation that covers each conductor. Typically, one color is a prominent background color of the insulation, and the other is a tracer, consisting of stripes, rings, or dots, applied over the background. The background color always matches the tracer color of its paired conductor, and vice vers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Blindness
Color blindness, color vision deficiency (CVD) or color deficiency is the decreased ability to color vision, see color or differences in color. The severity of color blindness ranges from mostly unnoticeable to full absence of color perception. Color blindness is usually a Sex linkage, sex-linked Heredity, inherited problem or variation in the functionality of one or more of the three classes of cone cells in the retina, which mediate color vision. The most common form is caused by a genetic condition called congenital red–green color blindness (including protan and deutan types), which affects ''up to'' 1 in 12 males (8%) and 1 in 200 females (0.5%). The condition is more prevalent in males, because the opsin genes responsible are located on the X chromosome. Rarer genetic conditions causing color blindness include congenital blue–yellow color blindness (tritan type), blue cone monochromacy, and achromatopsia. Color blindness can also result from physical or chemical dam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Angle
Visual angle is the angle a viewed object subtends at the eye, usually stated in degrees of arc. It also is called the object's angular size. The diagram on the right shows an observer's eye looking at a frontal extent (the vertical arrow) that has a linear size S, located in the distance D from point O. For present purposes, point O can represent the eye's nodal points at about the center of the lens, and also represent the center of the eye's entrance pupil that is only a few millimeters in front of the lens. The three lines from object endpoint A heading toward the eye indicate the bundle of light rays that pass through the cornea, pupil and lens to form an optical image of endpoint A on the retina at point a. The central line of the bundle represents the chief ray. The same holds for object point B and its retinal image at b. The visual angle V is the angle between the chief rays of A and B. Measuring and computing The visual angle V can be measured directly usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
