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Failsafe
In engineering, a fail-safe is a design feature or practice that in the event of a specific type of failure, inherently responds in a way that will cause minimal or no harm to other equipment, to the environment or to people. Unlike inherent safety to a particular hazard, a system being "fail-safe" does not mean that failure is impossible or improbable, but rather that the system's design prevents or mitigates unsafe consequences of the system's failure. That is, if and when a "fail-safe" system fails, it remains at least as safe as it was before the failure. Since many types of failure are possible, failure mode and effects analysis is used to examine failure situations and recommend safety design and procedures. Some systems can never be made fail-safe, as continuous availability is needed. Redundancy, fault tolerance, or contingency plans are used for these situations (e.g. multiple independently controlled and fuel-fed engines). Examples Mechanical or physical Examples inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Train
In rail transport, a train (from Old French , from Latin , "to pull, to draw") is a series of connected vehicles that run along a railway track and Passenger train, transport people or Rail freight transport, freight. Trains are typically pulled or pushed by locomotives (often known simply as "engines"), though some are self-propelled, such as multiple units. Passengers and cargo are carried in railroad cars, also known as wagons. Trains are designed to a certain Track gauge, gauge, or distance between rails. Most trains operate on steel tracks with steel wheels, the low friction of which makes them more efficient than other forms of transport. Trains have their roots in wagonways, which used railway tracks and were Horsecar, powered by horses or Cable railway, pulled by cables. Following the invention of the steam locomotive in the United Kingdom in 1804, trains rapidly spread around the world, allowing freight and passengers to move over land faster and cheaper than ever pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault Tolerance
Fault tolerance is the property that enables a system to continue operating properly in the event of the failure of one or more faults within some of its components. If its operating quality decreases at all, the decrease is proportional to the severity of the failure, as compared to a naively designed system, in which even a small failure can cause total breakdown. Fault tolerance is particularly sought after in high-availability, mission-critical, or even life-critical systems. The ability of maintaining functionality when portions of a system break down is referred to as graceful degradation. A fault-tolerant design enables a system to continue its intended operation, possibly at a reduced level, rather than failing completely, when some part of the system fails. The term is most commonly used to describe computer systems designed to continue more or less fully operational with, perhaps, a reduction in throughput or an increase in response time in the event of some partial fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineering
Engineering is the use of scientific method, scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The discipline of engineering encompasses a broad range of more specialized List of engineering branches, fields of engineering, each with a more specific emphasis on particular areas of applied mathematics, applied science, and types of application. See glossary of engineering. The term ''engineering'' is derived from the Latin ''ingenium'', meaning "cleverness" and ''ingeniare'', meaning "to contrive, devise". Definition The American Engineers' Council for Professional Development (ECPD, the predecessor of Accreditation Board for Engineering and Technology, ABET) has defined "engineering" as: The creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and even by industry. Further, both spellings are often used ''within'' a particular industry or country. Industries in British English-speaking countries typically use the "gauge" spelling. is the pressure relative to the ambient pressure. Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customary systems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as of this. Manometric u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Current Limiting
Current limiting is the practice of imposing a limit on the current that may be delivered to a load to protect the circuit generating or transmitting the current from harmful effects due to a short-circuit or overload. The term "current limiting" is also used to define a type of overcurrent protective device. According to the 2020 NEC/NFPA 70, a current limiting overcurrent protective device is defined as, "A device that, when interrupting currents in its current-limiting range, reduces the current flowing in the faulted circuit to a magnitude substantially less than that obtainable in the same circuit if the device were replaced with a solid conductor having compatible impedance." Inrush current limiting An inrush current limiter is a device or group of devices used to limit inrush current. Passive resistive components such as resistors or negative temperature coefficient (NTC) thermistors are simple options, with power dissipation and cool-down time being their main drawbacks, re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circuit Breaker
A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk of fire. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation. Circuit breakers are made in varying sizes, from small devices that protect low-current circuits or individual household appliances, to large switchgear designed to protect high voltage circuits feeding an entire city. The generic function of a circuit breaker, or fuse, as an automatic means of removing power from a faulty system, is often abbreviated as OCPD (Over Current Protection Device). Origins An early form of circuit breaker was described by Thomas Edison in an 1879 patent application, although his commercial power distribution system used fuses. Its purpose was to pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuse (electrical)
In electronics and electrical engineering, a fuse is an electrical safety device that operates to provide overcurrent protection of an electrical circuit. Its essential component is a metal wire or strip that melts when too much current flows through it, thereby stopping or interrupting the current. It is a sacrificial device; once a fuse has operated it is an open circuit, and must be replaced or rewired, depending on its type. Fuses have been used as essential safety devices from the early days of electrical engineering. Today there are thousands of different fuse designs which have specific current and voltage ratings, breaking capacity, and response times, depending on the application. The time and current operating characteristics of fuses are chosen to provide adequate protection without needless interruption. Wiring regulations usually define a maximum fuse current rating for particular circuits. Short circuits, overloading, mismatched loads, or device failure are the prime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Short Circuit
A short circuit (sometimes abbreviated to short or s/c) is an electrical circuit that allows a current to travel along an unintended path with no or very low electrical impedance. This results in an excessive current flowing through the circuit. The opposite of a short circuit is an "open circuit", which is an infinite resistance between two nodes. Definition A short circuit is an abnormal connection between two nodes of an electric circuit intended to be at different voltages. This results in an electric current limited only by the Thévenin equivalent resistance of the rest of the network which can cause circuit damage, overheating, fire or explosion. Although usually the result of a fault, there are cases where short circuits are caused intentionally, for example, for the purpose of voltage-sensing crowbar circuit protectors. In circuit analysis, a ''short circuit'' is defined as a connection between two nodes that forces them to be at the same voltage. In an 'ideal' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elevator
An elevator or lift is a wire rope, cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or deck (building), decks of a building, watercraft, vessel, or other structure. They are typically powered by electric motors that drive traction cables and counterweight systems such as a hoist (device), hoist, although some pump hydraulic fluid to raise a cylindrical piston like a hydraulic jack, jack. In agriculture and manufacturing, an elevator is any type of conveyor device used to lift materials in a continuous stream into bins or silos. Several types exist, such as the chain and bucket elevator, grain auger screw conveyor using the principle of Archimedes' screw, or the chain and paddles or forks of hay elevators. Languages other than English, such as Japanese, may refer to elevators by loanwords based on either ''elevator'' or ''lift''. Due to wheelchair access laws, elevators are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isolation Valve
An isolation valve is a valve in a fluid handling system that stops the flow of process media to a given location, usually for maintenance or safety purposes. They can also be used to provide flow logic (selecting one flow path versus another), and to connect external equipment to a system. A valve is classified as an isolation valve because of its intended function in a system, not because of the type of the valve itself. Therefore, many different types of valves can be classified as isolation valves. To easily understand the concept of an isolation valve, one can think of the valves ''under'' a kitchen or bathroom sink in a typical household. These valves are normally left open so that the user can control the flow of water with the spigot above the sink, and does not need to reach under the counter to start or stop the water flow. However, if the spigot needs to be replaced (i.e. maintenance needs to take place on the system), the isolation valves are shut to stop the flow o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Semaphore Signal
Railway semaphore signal is one of the earliest forms of fixed railway signals. This semaphore system involves signals that display their different indications to train drivers by changing the angle of inclination of a pivoted 'arm'. Semaphore signals were patented in the early 1840s by Joseph James Stevens, and soon became the most widely used form of mechanical signal. Designs have altered over the intervening years, and colour light signals have replaced semaphore signals in most countries, but in a few they remain in use. Origins The first railway semaphore signal was erected by Charles Hutton Gregory on the London and Croydon Railway (later the London Brighton and South Coast Railway) at New Cross, southeast London, about 1842 on the newly enlarged layout also accommodating the South Eastern Railway. John Urpeth Rastrick claimed to have suggested the idea to Hutton Gregory. The semaphore was afterwards rapidly adopted as fixed manual signals throughout Britain and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
130330 Thomas ELC And Wansbeck Railtour Northumberlandia 030
Thirteen or 13 may refer to: * 13 (number), the natural number following 12 and preceding 14 * One of the years 13 BC, AD 13, 1913, 2013 Music * 13AD (band), an Indian classic and hard rock band Albums * ''13'' (Black Sabbath album), 2013 * ''13'' (Blur album), 1999 * ''13'' (Borgeous album), 2016 * ''13'' (Brian Setzer album), 2006 * ''13'' (Die Ärzte album), 1998 * ''13'' (The Doors album), 1970 * ''13'' (Havoc album), 2013 * ''13'' (HLAH album), 1993 * ''13'' (Indochine album), 2017 * ''13'' (Marta Savić album), 2011 * ''13'' (Norman Westberg album), 2015 * ''13'' (Ozark Mountain Daredevils album), 1997 * ''13'' (Six Feet Under album), 2005 * ''13'' (Suicidal Tendencies album), 2013 * ''13'' (Solace album), 2003 * ''13'' (Second Coming album), 2003 * ''13'' (Ces Cru EP), 2012 * ''13'' (Denzel Curry EP), 2017 * ''Thirteen'' (CJ & The Satellites album), 2007 * ''Thirteen'' (Emmylou Harris album), 1986 * ''Thirteen'' (Harem Scarem album), 2014 * ''Thirt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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