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🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry

The MIM-104 Patriot is a surface-to-air missile (SAM) system, the primary of its kind used by the United States Army and several allied nations. It is manufactured by the U.S. defense contractor Raytheon and derives its name from the radar component of the weapon system. The AN/MPQ-53 at the heart of the system is known as the "Phased Array Tracking Radar to Intercept on Target" which is a backronym for PATRIOT. The Patriot System replaced the Nike Hercules system as the U.S. Army's primary High to Medium Air Defense (HIMAD) system, and replaced the MIM-23 Hawk system as the U.S. Army's medium tactical air defense system. In addition to these roles, Patriot has been given the function of the U.S. Army's anti-ballistic missile (ABM) system, which is now Patriot's primary mission. The system is expected to stay fielded until at least 2040.

Patriot uses an advanced aerial interceptor missile and high-performance radar systems. Patriot was developed at Redstone Arsenal in Huntsville, Alabama, which had previously developed the Safeguard ABM system and its component Spartan and hypersonic speed Sprint missiles. The symbol for Patriot is a drawing of a Revolutionary War-era Minuteman.

Patriot systems have been sold to the Netherlands, Poland, Germany, Egypt, Japan, Israel, Saudi Arabia, Kuwait, Republic of China (Taiwan), Greece, Spain, United Arab Emirates, Qatar and Romania. South Korea purchased several second-hand Patriot systems from Germany after North Korea test-launched ballistic missiles to the Sea of Japan and proceeded with underground nuclear testing in 2006. Jordan also purchased several second-hand Patriot systems from Germany. Poland hosts training rotations of a battery of U.S. Patriot launchers. This started in the town of Morąg in May 2010 but was later moved further from the Russian border to Toruń and Ustka due to Russian objections. On December 4, 2012, NATO authorized the deployment of Patriot missile launchers in Turkey to protect the country from missiles fired in the civil war in neighboring Syria. Patriot was one of the first tactical systems in the U.S. Department of Defense's (DoD) to employ lethal autonomy in combat.

The Patriot system gained notoriety during the Persian Gulf War of 1991 with the claimed engagement of over 40 Iraqi Scud missiles, but those claims became a source of controversy. The system was successfully used against Iraqi missiles in 2003 Iraq War, and has been also used by Saudi and Emirati forces in the Yemen conflict against Houthi missile attacks. The Patriot system achieved its first undisputed shootdowns of enemy aircraft in the service of the Israeli Air Defense Command. Israeli MIM-104D batteries shot down two Hamas UAVs during Operation Protective Edge on August 31, 2014 and later, on September 23, 2014, an Israeli Patriot battery shot down a Syrian Air Force Sukhoi Su-24 which had penetrated Israeli airspace, achieving the first shootdown of a manned enemy aircraft in the world for the system.

🔗 Computer science 🔗 Linguistics 🔗 Languages

Attempto Controlled English (ACE) is a controlled natural language, i.e. a subset of standard English with a restricted syntax and restricted semantics described by a small set of construction and interpretation rules. It has been under development at the University of Zurich since 1995. In 2013, ACE version 6.7 was announced.

ACE can serve as knowledge representation, specification, and query language, and is intended for professionals who want to use formal notations and formal methods, but may not be familiar with them. Though ACE appears perfectly natural – it can be read and understood by any speaker of English – it is in fact a formal language.

ACE and its related tools have been used in the fields of software specifications, theorem proving, text summaries, ontologies, rules, querying, medical documentation and planning.

Here are some simple examples:

1. Every woman is a human.
2. A woman is a human.
3. A man tries-on a new tie. If the tie pleases his wife then the man buys it.

ACE construction rules require that each noun be introduced by a determiner (a, every, no, some, at least 5, ...). Regarding the list of examples above, ACE interpretation rules decide that (1) is interpreted as universally quantified, while (2) is interpreted as existentially quantified. Sentences like "Women are human" do not follow ACE syntax and are consequently not valid.

Interpretation rules resolve the anaphoric references in (3): the tie and it of the second sentence refer to a new tie of the first sentence, while his and the man of the second sentence refer to a man of the first sentence. Thus an ACE text is a coherent entity of anaphorically linked sentences.

The Attempto Parsing Engine (APE) translates ACE texts unambiguously into discourse representation structures (DRS) that use a variant of the language of first-order logic. A DRS can be further translated into other formal languages, for instance AceRules with various semantics, OWL, and SWRL. Translating an ACE text into (a fragment of) first-order logic allows users to reason about the text, for instance to verify, to validate, and to query it.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/Military science, technology, and theory 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Military history/European military history 🔗 Military history/British military history

The Battle of the Beams was a period early in the Second World War when bombers of the German Air Force (Luftwaffe) used a number of increasingly accurate systems of radio navigation for night bombing in the United Kingdom. British scientific intelligence at the Air Ministry fought back with a variety of their own increasingly effective means, involving jamming and distortion of the radio waves. The period ended when the Wehrmacht moved their forces to the East in May 1941, in preparation for the attack on the Soviet Union.

🔗 Technology 🔗 Engineering 🔗 Sweden

The Mecanum wheel is a omnidirectional wheel design for a land-based vehicle to move in any direction. It is sometimes called the Ilon wheel after its inventor, Bengt Erland Ilon (1923-2008), who came up with the concept while working as an engineer with the Swedish company Mecanum AB, and patented it in the United States on November 13, 1972.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Websites

VRML (Virtual Reality Modeling Language, pronounced vermal or by its initials, originally—before 1995—known as the Virtual Reality Markup Language) is a standard file format for representing 3-dimensional (3D) interactive vector graphics, designed particularly with the World Wide Web in mind. It has been superseded by X3D.

🔗 Industrial design

In industrial design, preferred numbers (also called preferred values or preferred series) are standard guidelines for choosing exact product dimensions within a given set of constraints. Product developers must choose numerous lengths, distances, diameters, volumes, and other characteristic quantities. While all of these choices are constrained by considerations of functionality, usability, compatibility, safety or cost, there usually remains considerable leeway in the exact choice for many dimensions.

Preferred numbers serve two purposes:

1. Using them increases the probability of compatibility between objects designed at different times by different people. In other words, it is one tactic among many in standardization, whether within a company or within an industry, and it is usually desirable in industrial contexts (unless the goal is vendor lock-in or planned obsolescence)
2. They are chosen such that when a product is manufactured in many different sizes, these will end up roughly equally spaced on a logarithmic scale. They therefore help to minimize the number of different sizes that need to be manufactured or kept in stock.

Preferred numbers represent preferences of simple numbers (such as 1, 2, and 5) multiplied by the powers of a convenient basis, usually 10.

🔗 Soviet Union 🔗 Russia 🔗 Death 🔗 Guild of Copy Editors 🔗 Russia/physical geography of Russia 🔗 Russia/history of Russia 🔗 Russia/sports and games in Russia

The Dyatlov Pass incident (Russian: Гибель тургруппы Дятлова) was an event where nine Russian hikers died in the northern Ural Mountains between 1 and 2 February 1959, in uncertain circumstances. The experienced trekking group, who were all from the Ural Polytechnical Institute, had established a camp on the slopes of Kholat Syakhl, in an area now named in honor of the group's leader, Igor Dyatlov. During the night, something caused them to tear their way out of their tents and flee the campsite, all while inadequately dressed for the heavy snowfall and sub-zero temperatures.

After the group's bodies were discovered, an investigation by Soviet authorities determined that six had died from hypothermia while the other three showed signs of physical trauma. One victim had a fractured skull; two others had major chest fractures and the body of one of the group was missing both its eyes. One of the victims was missing a tongue. The investigation concluded that a "compelling natural force" had caused the deaths. Numerous theories have been put forward to account for the unexplained deaths, including animal attacks, hypothermia, avalanche, katabatic winds, infrasound-induced panic, military involvement, or some combination of these.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Aviation/Aviation accident 🔗 Wiltshire 🔗 Military history/European military history 🔗 Military history/British military history

On 22 July 1966 Walter "Taffy" Holden, an engineer in command of No. 33 Maintenance Unit RAF with limited experience flying small single-engine trainer aircraft, inadvertently engaged the afterburner of a Mach 2.0-capable English Electric Lightning during ground testing. Unable to disengage the afterburner, Holden ran down the runway, narrowly missing a crossing fuel bowser and a de Havilland Comet taking off, before taking off himself. Flying without a helmet or canopy, the ejection seat disabled, and the landing gear locked down, Holden aborted his first two landing attempts. He landed on his third approach, striking the runway with the aircraft's tail as he adopted in his flare the attitude of a taildragger aircraft. The aircraft returned to service, and was subsequently acquired by the Imperial War Museum Duxford.