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🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry

The Lazy Dog (sometimes called a Red Dot Bomb or Yellow Dog Bomb) is a type of small, unguided kinetic projectile used by the U.S. Air Force. It measured about 1.75 inches (44 mm) in length, 0.5 inches (13 mm) in diameter, and weighed about 0.7 ounces (20 g).

The weapons were designed to be dropped from an aircraft. They contained no explosive charge but as they fell they would develop significant kinetic energy making them lethal and able to easily penetrate soft cover such as jungle canopy, several inches of sand, or light armor. Lazy Dog munitions were simple and relatively cheap; they could be dropped in huge numbers in a single pass. Though their effects were often no less deadly than other projectiles, they did not leave unexploded ordnance (UXO) that could be active years after a conflict ended.

Lazy Dog projectiles were used primarily during the Korean and the Vietnam Wars.

🔗 United States 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 United States/Military history - U.S. military history 🔗 Military history/Intelligence 🔗 Military history/Maritime warfare 🔗 Ships 🔗 Israel 🔗 Palestine 🔗 Military history/Middle Eastern military history

The USS Liberty incident was an attack on a United States Navy technical research ship (spy ship), USS Liberty, by Israeli Air Force jet fighter aircraft and Israeli Navy motor torpedo boats, on 8 June 1967, during the Six-Day War. The combined air and sea attack killed 34 crew members (naval officers, seamen, two marines, and one civilian NSA employee), wounded 171 crew members, and severely damaged the ship. At the time, the ship was in international waters north of the Sinai Peninsula, about 25.5 nautical miles (47.2 km; 29.3 mi) northwest from the Egyptian city of Arish.

Israel apologized for the attack, saying that the USS Liberty had been attacked in error after being mistaken for an Egyptian ship. Both the Israeli and U.S. governments conducted inquiries and issued reports that concluded the attack was a mistake due to Israeli confusion about the ship's identity. Others, including survivors of the attack, have rejected these conclusions and maintain that the attack was deliberate.

In May 1968, the Israeli government paid US$3.32 million (equivalent to US$29.1 million in 2023) to the U.S. government in compensation for the families of the 34 men killed in the attack. In March 1969, Israel paid a further $3.57 million ($29.6 million in 2023) to the men who had been wounded. In December 1980, it agreed to pay $6 million ($22.2 million in 2023) as the final settlement for material damage to the ship plus 13 years of interest.

🔗 France 🔗 Military history 🔗 British Empire 🔗 Military history/French military history 🔗 Military history/Cold War 🔗 Colonialism 🔗 Egypt 🔗 Israel 🔗 Palestine 🔗 Military history/Middle Eastern military history 🔗 Military history/European military history 🔗 Military history/British military history

The Suez Crisis or the Second Arab–Israeli War, also referred to as the Tripartite Aggression in the Arab world and as the Sinai War in Israel, was a British–French–Israeli invasion of Egypt in 1956. Israel invaded on 29 October, having done so with the primary objective of re-opening the Straits of Tiran and the Gulf of Aqaba as the recent tightening of the eight-year-long Egyptian blockade further prevented Israeli passage. After issuing a joint ultimatum for a ceasefire, the United Kingdom and France joined the Israelis on 5 November, seeking to depose Egyptian president Gamal Abdel Nasser and regain control of the Suez Canal, which Nasser had earlier nationalised by transferring administrative control from the foreign-owned Suez Canal Company to Egypt's new government-owned Suez Canal Authority. Shortly after the invasion began, the three countries came under heavy political pressure from both the United States and the Soviet Union, as well as from the United Nations, eventually prompting their withdrawal from Egypt. Israel's four-month-long occupation of the Egyptian-occupied Gaza Strip and Egypt's Sinai Peninsula enabled it to attain freedom of navigation through the Straits of Tiran, but the Suez Canal itself was closed from October 1956 to March 1957. The Suez Crisis led to international humiliation for the British and the French in the wake of the Cold War, which established the Americans and the Soviets as the world's superpowers. It also strengthened Nasser's standing.

Before they were defeated, Egyptian troops had blocked all ship traffic by sinking 40 ships in the Suez Canal. It later became clear that Israel, the United Kingdom, and France had conspired to invade Egypt. Though the three allies had attained a number of their military objectives, the Suez Canal itself was useless. American president Dwight D. Eisenhower had issued a strong warning to the British if they were to invade Egypt; he threatened serious damage to the British financial system by selling the American government's bonds of pound sterling. Historians have concluded that the Suez Crisis "signified the end of Great Britain's role as one of the world's major powers" vis-à-vis the United States and the Soviet Union.

As a result of the conflict, the United Nations established the United Nations Emergency Force to police and patrol the Egypt–Israel border, while British prime minister Anthony Eden resigned from his position. For his diplomatic efforts in resolving the conflict through United Nations initiatives, Canadian external affairs minister Lester B. Pearson received a Nobel Peace Prize. Analysts have argued that the Suez Crisis may have emboldened the Soviet Union, prompting the Soviet invasion of Hungary.

🔗 Computing 🔗 Computer science

The Rete algorithm ( REE-tee, RAY-tee, rarely REET, reh-TAY) is a pattern matching algorithm for implementing rule-based systems. The algorithm was developed to efficiently apply many rules or patterns to many objects, or facts, in a knowledge base. It is used to determine which of the system's rules should fire based on its data store, its facts. The Rete algorithm was designed by Charles L. Forgy of Carnegie Mellon University, first published in a working paper in 1974, and later elaborated in his 1979 Ph.D. thesis and a 1982 paper.

A milk watcher, milk saver, pot watcher, pot minder, milk guard, or boil over preventer is a cooking utensil placed at the bottom of a pot to prevent the foaming boil-over of liquids by collecting small bubbles of steam into one large bubble.

🔗 History 🔗 Economics 🔗 Philosophy 🔗 Business 🔗 Philosophy/Ethics

A perverse incentive is an incentive that has an unintended and undesirable result that is contrary to the intentions of its designers. The cobra effect is the most direct kind of perverse incentive, typically because the incentive unintentionally rewards people for making the issue worse. The term is used to illustrate how incorrect stimulation in economics and politics can cause unintended consequences.

🔗 Physics

A Halbach array (German: [ˈhalbax]) is a special arrangement of permanent magnets that augments the magnetic field on one side of the array while cancelling the field to near zero on the other side. This is achieved by having a spatially rotating pattern of magnetisation.

The rotating pattern of permanent magnets (on the front face; on the left, up, right, down) can be continued indefinitely and have the same effect. The effect of this arrangement is roughly similar to many horseshoe magnets placed adjacent to each other, with similar poles touching.

This magnetic orientation process replicates that applied by a magnetic recording tape head to the magnetic tape coating during the recording process. The principle was further described by James (Jim) M. Winey of Magnepan in 1970, for the ideal case of continuously rotating magnetization, induced by a one-sided stripe-shaped coil.

The effect was also discovered by John C. Mallinson in 1973, and these "one-sided flux" structures were initially described by him as a "curiosity", although at the time he recognized from this discovery the potential for significant improvements in magnetic tape technology.

Physicist Klaus Halbach, while at the Lawrence Berkeley National Laboratory during the 1980s, independently invented the Halbach array to focus particle accelerator beams.

🔗 Medicine 🔗 Biology

The blue field entoptic phenomenon is an entoptic phenomenon characterized by the appearance of tiny bright dots (nicknamed blue-sky sprites) moving quickly along undulating pathways in the visual field, especially when looking into bright blue light such as the sky. The dots are short-lived, visible for about one second or less, and traveling short distances along seemingly random, undulating paths. Some of them seem to follow the same path as other dots before them. The dots may appear elongated along the path, like tiny worms. The dots' rate of travel appears to vary in synchrony with the heartbeat: they briefly accelerate at each beat. The dots appear in the central field of view, within 15 degrees from the fixation point. The left and right eye see different, seemingly random, dot patterns; a person viewing through both eyes sees a combination of both left and right visual field disturbances. While seeing the phenomenon, lightly pressing inward on the sides of the eyeballs at the lateral canthus causes the movement to stop being fluid and the dots to move only when the heart beats.

Most people are able to see this phenomenon in the sky, although it is relatively weak in most instances; many will not notice it until asked to pay attention. The dots are highly conspicuous against any monochromatic blue background of a wavelength of around 430 nm in place of the sky. The phenomenon is also known as Scheerer's phenomenon, after the German ophthalmologist Richard Scheerer, who first drew clinical attention to it in 1924.

🔗 International relations 🔗 Technology 🔗 Internet 🔗 Computing 🔗 Computer science 🔗 Law 🔗 Business 🔗 Politics 🔗 Robotics 🔗 International relations/International law 🔗 Futures studies 🔗 European Union 🔗 Science Policy 🔗 Artificial Intelligence

The Artificial Intelligence Act (AI Act) is a European Union regulation concerning artificial intelligence (AI).

It establishes a common regulatory and legal framework for AI in the European Union (EU). Proposed by the European Commission on 21 April 2021, and then passed in the European Parliament on 13 March 2024, it was unanimously approved by the Council of the European Union on 21 May 2024. The Act creates a European Artificial Intelligence Board to promote national cooperation and ensure compliance with the regulation. Like the EU's General Data Protection Regulation, the Act can apply extraterritorially to providers from outside the EU, if they have users within the EU.

It covers all types of AI in a broad range of sectors; exceptions include AI systems used solely for military, national security, research and non-professional purposes. As a piece of product regulation, it would not confer rights on individuals, but would regulate the providers of AI systems and entities using AI in a professional context. The draft Act was revised following the rise in popularity of generative AI systems, such as ChatGPT, whose general-purpose capabilities did not fit the main framework. More restrictive regulations are planned for powerful generative AI systems with systemic impact.

The Act classifies AI applications by their risk of causing harm. There are four levels – unacceptable, high, limited, minimal – plus an additional category for general-purpose AI. Applications with unacceptable risks are banned. High-risk applications must comply with security, transparency and quality obligations and undergo conformity assessments. Limited-risk applications only have transparency obligations and those representing minimal risks are not regulated. For general-purpose AI, transparency requirements are imposed, with additional evaluations when there are high risks.

La Quadrature du Net (LQDN) stated that the adopted version of the AI Act would be ineffective, arguing that the role of self-regulation and exemptions in the act rendered it "largely incapable of standing in the way of the social, political and environmental damage linked to the proliferation of AI".

🔗 Physics 🔗 Astronomy

A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of low mass stars (between 0.8 solar masses (M_☉) and 2.0 M_☉) during their red giant phase. The Sun is predicted to experience a flash 1.2 billion years after it leaves the main sequence. A much rarer runaway helium fusion process can also occur on the surface of accreting white dwarf stars.

Low-mass stars do not produce enough gravitational pressure to initiate normal helium fusion. As the hydrogen in the core is exhausted, some of the helium left behind is instead compacted into degenerate matter, supported against gravitational collapse by quantum mechanical pressure rather than thermal pressure. Subsequent hydrogen shell fusion further increases the mass of the core until it reaches temperature of approximately 100 million kelvin, which is hot enough to initiate helium fusion (or "helium burning") in the core.

However, a fundamental quality of degenerate matter is that increases in temperature do not produce an increase in the pressure of the matter until the thermal pressure becomes so very high that it exceeds degeneracy pressure. In main sequence stars, thermal expansion regulates the core temperature, but in degenerate cores, this does not occur. Helium fusion increases the temperature, which increases the fusion rate, which further increases the temperature in a runaway reaction which quickly spans the entire core. This produces a flash of very intense helium fusion that lasts only a few minutes, but during that time, produces energy at a rate comparable to the entire Milky Way galaxy.

In the case of normal low-mass stars, the vast energy release causes much of the core to come out of degeneracy, allowing it to thermally expand. This consumes most of the total energy released by the helium flash, and any left-over energy is absorbed into the star's upper layers. Thus the helium flash is mostly undetectable by observation, and is described solely by astrophysical models. After the core's expansion and cooling, the star's surface rapidly cools and contracts in as little as 10,000 years until it is roughly 2% of its former radius and luminosity. It is estimated that the electron-degenerate helium core weighs about 40% of the star mass and that 6% of the core is converted into carbon.