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🔗 Aviation

Bitching Betty is a slang term used by some pilots and aircrew (mainly North American), when referring to the voices used by some aircraft warning systems.

The enunciating voice, in at least some aircraft systems, may be either male or female and in some cases this may be selected according to pilot preference. If the voice is female, it may be referred to as Bitching Betty; if the voice is male, it may be referred to as Barking Bob. A female voice is heard on military aircraft such as the F-16 Fighting Falcon, the Eurofighter Typhoon and the Mikoyan MiG-29. A male voice is heard on Boeing commercial airliners and is also used in the BAE Hawk.

In the United Kingdom the term Nagging Nora is sometimes used, and in New Zealand the term used for Boeing aircraft is Hank the Yank. The voice warning system used on London Underground trains, which also uses a female voice, is known to some staff as Sonya, as it "gets on ya nerves".

🔗 Classical Greece and Rome 🔗 Greece 🔗 Trains 🔗 Archaeology

The Diolkos (Δίολκος, from the Greek διά, dia "across" and ὁλκός, holkos "portage machine") was a paved trackway near Corinth in Ancient Greece which enabled boats to be moved overland across the Isthmus of Corinth. The shortcut allowed ancient vessels to avoid the long and dangerous circumnavigation of the Peloponnese peninsula. The phrase "as fast as a Corinthian", penned by the comic playwright Aristophanes, indicates that the trackway was common knowledge and had acquired a reputation for swiftness.

The main function of the Diolkos was the transfer of goods, although in times of war it also became a preferred means of speeding up naval campaigns. The 6 km (3.7 mi) to 8.5 km (5.3 mi) long roadway was a rudimentary form of railway, and operated from c. 600 BC until the middle of the 1st century AD. The scale on which the Diolkos combined the two principles of the railway and the overland transport of ships remained unique in antiquity.

🔗 Business 🔗 Urban studies and planning 🔗 Cities

A company town is a place where practically all stores and housing are owned by the one company that is also the main employer. Company towns are often planned with a suite of amenities such as stores, houses of worship, schools, markets and recreation facilities. They are usually bigger than a model village ("model" in the sense of an ideal to be emulated).

Some company towns have had high ideals, but many have been regarded as controlling and/or exploitative. Others developed more or less in unplanned fashion, such as Summit Hill, Pennsylvania, United States, one of the oldest, which began as an LC&N Co. mining camp and mine site nine miles (14.5 km) from the nearest outside road.

🔗 Physics

Flux pinning is the phenomenon where a superconductor is pinned in space above a magnet. The superconductor must be a type-II superconductor because type-I superconductors cannot be penetrated by magnetic fields. The act of magnetic penetration is what makes flux pinning possible. At higher magnetic fields (above Hc1 and below Hc2) the superconductor allows magnetic flux to enter in quantized packets surrounded by a superconducting current vortex (see Quantum vortex). These sites of penetration are known as flux tubes. The number of flux tubes per unit area is proportional to the magnetic field with a constant of proportionality equal to the magnetic flux quantum. On a simple 76 millimeter diameter, 1-micrometer thick disk, next to a magnetic field of 28 kA/m, there are approximately 100 billion flux tubes that hold 70,000 times the superconductor's weight. At lower temperatures the flux tubes are pinned in place and cannot move. This pinning is what holds the superconductor in place thereby allowing it to levitate. This phenomenon is closely related to the Meissner effect, though with one crucial difference — the Meissner effect shields the superconductor from all magnetic fields causing repulsion, unlike the pinned state of the superconductor disk which pins flux, and the superconductor in place.

🔗 Computing 🔗 Computing/Computer hardware 🔗 Computing/Computer Security

A Kensington Security Slot (also called a K-Slot or Kensington lock) is part of an anti-theft system designed in the early 1990s and patented by Kryptonite in 1999–2000, assigned to Schlage in 2002, and since 2005 owned and marketed by Kensington Computer Products Group, a division of ACCO Brands.

🔗 Russia 🔗 Russia/technology and engineering in Russia 🔗 Russia/mass media in Russia 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Intelligence 🔗 Military history/Russian, Soviet and CIS military history 🔗 Radio Stations

UVB-76, also known as "The Buzzer", is a nickname given by radio listeners to a shortwave radio station that broadcasts on the frequencies 4625 and 4810 kHz. It broadcasts a short, monotonous buzz tone , repeating at a rate of approximately 25 tones per minute, 24 hours per day. Sometimes, the buzzer signal is interrupted and a voice transmission in Russian takes place. The first reports were made of a station on this frequency in 1973.

🔗 Environment 🔗 Disaster management 🔗 Mexico 🔗 Occupational Safety and Health 🔗 Energy 🔗 Caribbean 🔗 Fisheries and Fishing

Ixtoc I was an exploratory oil well being drilled by the semi-submersible drilling rig Sedco 135 in the Bay of Campeche of the Gulf of Mexico, about 100 km (62 mi) northwest of Ciudad del Carmen, Campeche in waters 50 m (160 ft) deep. On 3 June 1979, the well suffered a blowout resulting in one of the largest oil spills in history.

🔗 Physics

In quantum mechanics, the Kochen–Specker (KS) theorem, also known as the Bell–Kochen–Specker theorem, is a "no-go" theorem proved by John S. Bell in 1966 and by Simon B. Kochen and Ernst Specker in 1967. It places certain constraints on the permissible types of hidden-variable theories, which try to explain the predictions of quantum mechanics in a context-independent way. The version of the theorem proved by Kochen and Specker also gave an explicit example for this constraint in terms of a finite number of state vectors.

The theorem is a complement to Bell's theorem (to be distinguished from the (Bell–)Kochen–Specker theorem of this article). While Bell's theorem established nonlocality to be a feature of any hidden variable theory that recovers the predictions of quantum mechanics, the KS theorem established contextuality to be an inevitable feature of such theories.

The theorem proves that there is a contradiction between two basic assumptions of the hidden-variable theories intended to reproduce the results of quantum mechanics: that all hidden variables corresponding to quantum-mechanical observables have definite values at any given time, and that the values of those variables are intrinsic and independent of the device used to measure them. The contradiction is caused by the fact that quantum-mechanical observables need not be commutative. It turns out to be impossible to simultaneously embed all the commuting subalgebras of the algebra of these observables in one commutative algebra, assumed to represent the classical structure of the hidden-variables theory, if the Hilbert space dimension is at least three.

The Kochen–Specker theorem excludes hidden-variable theories that assume that elements of physical reality can all be consistently represented simultaneously by the quantum mechanical Hilbert space formalism disregarding the context of a particular framework (technically a projective decomposition of the identity operator) related to the experiment or analytical viewpoint under consideration. As succinctly worded by Isham and Butterfield, (under the assumption of a universal probabilistic sample space as in non-contextual hidden variable theories) the Kochen–Specker theorem "asserts the impossibility of assigning values to all physical quantities whilst, at the same time, preserving the functional relations between them".

🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Cold War

The Battle of Palmdale was the attempted shoot-down of a runaway drone by United States Air Force interceptors in the skies over Southern California in mid-August 1956. The drone was launched from Point Mugu Naval Air Station and soon went out of control. Interceptor aircraft took off from Oxnard Air Force Base and caught up with the drone, but were ultimately unable to bring it down, in spite of expending all of their rockets. After it ran out of fuel, the unmanned aircraft crashed in a sparsely populated tract of desert.

During the incident over 1000 acres were scorched and a substantial amount of property was damaged or destroyed.

🔗 Books 🔗 Maps

An Atlas of Fantasy, compiled by Jeremiah Benjamin Post, was originally published in 1973 by Mirage Press and revised for a 1979 edition by Ballantine Books. The 1979 edition dropped twelve maps from the first edition and added fourteen new ones. It also included an introduction by Lester del Rey.

To remain of manageable size, the Atlas excludes advertising maps, cartograms, most disproportionate maps, and alternate history ("might have been") maps, focusing instead on imaginary lands derived from literary sources. It purposefully omits "one-to-one" maps such as Thomas Hardy's Wessex (which merely renames places in southwest England), but includes Barsetshire and Yoknapatawpha County, which are evidently considered to be sufficiently fictionalized. The emphasis is on science fiction and fantasy, though Post suggests there exist enough mystery fiction maps to someday create The Detectives' Handy Pocket Atlas. Other maps were omitted due to permission costs or reproduction quality.

The maps are reproduced from many sources, and an Index of Artists is included.