|
Dead Man's Switch
A dead man's switch is a switch that is designed to be activated or deactivated if the human operator becomes incapacitated, such as through death, loss of consciousness, or being bodily removed from control. Originally applied to switches on a vehicle or machine, it has since come to be used to describe other intangible uses, as in computer software. These switches are usually used as a form of fail-safe where they stop a machine with no operator from a potentially dangerous action or incapacitate a device as a result of accident, malfunction, or misuse. They are common in such applications as locomotives, aircraft refuelling, freight elevators, lawn mowers, tractors, personal watercraft, outboard motors, chainsaws, snowblowers, treadmills, snowmobiles, amusement rides, and many medical imaging devices. On some machines, these switches merely bring the machines back to a safe state, such as reducing the throttle to idle or applying brakes while leaving the machines still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fail-deadly
Fail-deadly is a concept in nuclear military strategy that encourages deterrence by guaranteeing an immediate, automatic, and overwhelming response to an attack, even if there is no one left to trigger such retaliation. The term ''fail-deadly'' was coined as a contrast to ''fail-safe''. Fail-deadly can refer to specific technology components, or the controls system as a whole. The United Kingdom's fail-deadly policies delegate strike authority to submarine commanders in the event of a loss of command (using letters of last resort), ensuring that even when uncoordinated, nuclear retaliation can be carried out. See also * AN/DRC-8 Emergency Rocket Communications System * * * '' Dr. Strangelove'' * * * Mutual assured destruction (MAD) * * * Two Generals' Problem * Dead Hand Dead Hand, also known as Perimeter (, with the GRAU Index 15E601, Cyrillic script, Cyrillic: 15Э601), is a Cold War–era automatic or semi-automatic nuclear weapons control system (similar in co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brake
A brake is a machine, mechanical device that inhibits motion by absorbing energy from a moving system. It is used for Acceleration, slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. Background Most brakes commonly use friction between two surfaces pressed together to convert the kinetic energy of the moving object into heat, though other methods of energy conversion may be employed. For example, regenerative braking converts much of the energy to electrical energy, which may be stored for later use. Other methods convert kinetic energy into potential energy in such stored forms as Compressed air energy storage, pressurized air or pressurized oil. Eddy current brakes use magnetic fields to convert kinetic energy into electric current in the brake disc, fin, or rail, which is converted into heat. Still other braking methods even transform kinetic energy into different forms, for example by transferring the en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PCC Streetcar
The Presidents' Conference Committee (PCC) is a streetcar (tram) design that was first built in the United States in the 1930s. The design proved successful domestically, and after World War II it was licensed for use elsewhere in the world where PCC based cars were made. The PCC car has proved to be a long-lasting icon of streetcar design. Approximately 5,000 PCC streetcars were built in the United States, with production continuing until 1952. In North America, some PCC streetcars are still in regular service, with most operating on heritage streetcar lines. , the San Francisco Municipal Railway is the largest North American operator of PCC cars, using a fleet of 27 on two heritage lines. After World War II, the PCC design was licensed to multiple European companies. Over 15,000 PCC-derived streetcars were built in Europe, including the popular Tatra T3. Origins The Presidents' Conference Committee (PCC) originated from the design committee formed in 1929. It was renamed t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streetcar
A tram (also known as a streetcar or trolley in Canada and the United States) is an urban rail transit in which vehicles, whether individual railcars or multiple-unit trains, run on tramway tracks on urban public streets; some include segments on segregated right-of-way. The tramlines or tram networks operated as public transport are called tramways or simply trams/streetcars. Because of their close similarities, trams are commonly included in the wider term '' light rail'', which also includes systems separated from other traffic. Tram vehicles are usually lighter and shorter than main line and rapid transit trains. Most trams use electrical power, usually fed by a pantograph sliding on an overhead line; older systems may use a trolley pole or a bow collector. In some cases, a contact shoe on a third rail is used. If necessary, they may have dual power systems—electricity in city streets and diesel in more rural environments. Occasionally, trams also carry frei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birney
A Birney or Birney Safety Car is a type of streetcar that was manufactured in the United States in the 1910s and 1920s. The design was small and light and was intended to be an economical means of providing frequent service at a lower infrastructure and labour (economics), labor cost than conventional streetcars. Production of Birney cars lasted from 1915 until 1930, and more than 6,000 of the original, single-Bogie, truck version were built.William D. Middleton, Middleton, William D. (1967). ''The Time of the Trolley'', pp. 122–127, 210, 414. Milwaukee: Kalmbach Publishing. . Several different manufacturers built Birney cars. The design was "the first mass-produced standard streetcar (albeit with minor variations)" in North America. Invention The Birney car was the joint 1915 invention of Charles Birney and Joseph Bosenbury (who was issued the patents in 1917 and 1919, and assigned half to Birney; see Brill page 140). Birney was an engineer with the firm of Stone & Webster, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapid Transit
Rapid transit or mass rapid transit (MRT) or heavy rail, commonly referred to as metro, is a type of high-capacity public transport that is generally built in urban areas. A grade separation, grade separated rapid transit line below ground surface through a tunnel can be regionally called a subway, tube, metro or underground. They are sometimes grade-separated on elevated railways, in which case some are referred to as el trains – short for "elevated" – or skytrains. Rapid transit systems are usually electric railway, electric railways, that unlike buses or trams operate on an exclusive right-of-way (transportation), right-of-way, which cannot be accessed by pedestrians or other vehicles. Modern services on rapid transit systems are provided on designated lines between metro station, stations typically using electric multiple units on railway tracks. Some systems use rubber-tyred metro, guided rubber tires, magnetic levitation (''maglev''), or monorail. The stations typica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tram
A tram (also known as a streetcar or trolley in Canada and the United States) is an urban rail transit in which Rolling stock, vehicles, whether individual railcars or multiple-unit trains, run on tramway tracks on urban public streets; some include segments on segregated Right-of-way (property access), right-of-way. The tramlines or tram networks operated as public transport are called tramways or simply trams/streetcars. Because of their close similarities, trams are commonly included in the wider term ''light rail'', which also includes systems separated from other traffic. Tram vehicles are usually lighter and shorter than Main line (railway), main line and rapid transit trains. Most trams use electrical power, usually fed by a Pantograph (transport), pantograph sliding on an overhead line; older systems may use a trolley pole or a bow collector. In some cases, a contact shoe on a third rail is used. If necessary, they may have dual power systems—electricity in city stre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kill Switch
A kill switch, also known more formally as an emergency brake, emergency stop (E-stop), emergency off (EMO), or emergency power off (EPO), is a safety mechanism used to shut off machinery in an emergency, when it cannot be shut down in the usual manner. Unlike a normal shut-down switch or shut-down procedure, which shuts down all systems in order and turns off the machine without damage, a kill switch is designed and configured to abort the operation as quickly as possible (even if it damages the equipment) and to be operated simply and quickly (so that even a panicked operator with impaired executive functions or a bystander can activate it). Kill switches are usually designed to be noticeable, even to an untrained operator or a bystander. Some kill switches feature a removable, protective barrier against accidental activation (e.g. a plastic cover that must be lifted or glass that must be broken), known as a mollyguard. Kill switches are features of mechanisms whose normal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vault 7
Vault 7 is a series of documents that WikiLeaks began to publish on 7 March 2017, detailing the activities and capabilities of the United States Central Intelligence Agency (CIA) to perform electronic surveillance and cyber warfare. The files, dating from 2013 to 2016, include details on the agency's software capabilities, such as the ability to compromise cars, smart TVs, web browsers including Google Chrome, Microsoft Edge, Mozilla Firefox, and Opera, the operating systems of most smartphones including Apple's iOS and Google's Android, and computer operating systems including Microsoft Windows, macOS, and Linux. A CIA internal audit identified 91 malware tools out of more than 500 tools in use in 2016 being compromised by the release. The tools were developed by the Operations Support Branch of the CIA. The Vault 7 release led the CIA to redefine WikiLeaks as a "non-state hostile intelligence service." In July 2022, former CIA software engineer Joshua Schulte was convicted of l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistic Missile Submarines
A ballistic missile submarine is a submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads. These submarines became a major weapon system in the Cold War because of their deterrence theory, nuclear deterrence capability. They can fire missiles thousands of kilometers from their targets, and acoustic quieting makes them difficult to detect (see acoustic signature), thus making them a survivable deterrent in the event of a Pre-emptive nuclear strike, first strike and a key element of the mutual assured destruction policy of nuclear deterrence. The deployment of ballistic missile submarines is dominated by the United States, Russia (following the collapse of the Soviet Union) and China. In fact, 70% of nuclear warheads in the USA are carried by ballistic missile submarines.Rafal, A. S. (2021). THE FUTURE OF SUBMARINE WARFARE: NUCLEAR POWERED SUBMARINES ARE THE BEDROCK OF NAVAL WARFARE, OR MAYBE NOT. MS Thesis. Joint Forces Staff College ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prime Minister Of The United Kingdom
The prime minister of the United Kingdom is the head of government of the United Kingdom. The prime minister Advice (constitutional law), advises the Monarchy of the United Kingdom, sovereign on the exercise of much of the Royal prerogative in the United Kingdom, royal prerogative, chairs the Cabinet of the United Kingdom, Cabinet, and selects its Minister of the Crown, ministers. Modern prime ministers hold office by virtue of their ability to command the confidence of the House of Commons of the United Kingdom, House of Commons, so they are invariably Member of Parliament (United Kingdom), members of Parliament. The office of prime minister is not established by any statute or constitutional document, but exists only by long-established Constitutional conventions of the United Kingdom, convention, whereby the monarch appoints as prime minister the person most likely to Confidence motions in the United Kingdom, command the confidence of the House of Commons. In practice, thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
