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🔗 Biography 🔗 Biography/Musicians 🔗 Jazz

Louis Thomas Hardin (May 26, 1916 – September 8, 1999), also known as Moondog, was an American musician, composer, theoretician, poet and inventor of several musical instruments. He was blind from the age of 16.

Hardin lived in New York City from the late 1940s until 1972, and during this time he could often be found on 6th Avenue, between 52nd and 55th Streets, wearing a cloak and a horned helmet sometimes busking or selling music, but often just standing silently on the sidewalk. He was widely recognized as "the Viking of 6th Avenue" by thousands of passersby and residents who were not aware of his musical career.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Law 🔗 Tennessee

The Battle of Athens (sometimes called the McMinn County War) was a rebellion led by citizens in Athens and Etowah, Tennessee, United States, against the local government in August 1946. The citizens, including some World War II veterans, accused the local officials of predatory policing, police brutality, political corruption, and voter intimidation.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Military history/Cold War 🔗 Pritzker Military Library 🔗 Firearms

The M-28 or M-29 Davy Crockett Weapon System was the tactical nuclear recoilless gun (smoothbore) for firing the M-388 nuclear projectile that was deployed by the United States during the Cold War. It was one of the smallest nuclear weapon systems ever built, with a yield between 10 and 20 tons TNT equivalent (40–80 gigajoules). It is named after American folk hero, soldier, and congressman Davy Crockett.

🔗 Spaceflight

StarTram is a proposed space launch system propelled by maglev. The initial Generation 1 facility would launch cargo only, launching from a mountain peak at an altitude of 3 to 7 kilometres (1.9 to 4.3 mi) with an evacuated tube staying at local surface level; it has been claimed that about 150,000 tons could be lifted to orbit annually. More advanced technology would be required for the Generation 2 system for passengers, with a longer track instead gradually curving up at its end to the thinner air at 22 kilometres (14 mi) altitude, supported by magnetic levitation, reducing g-forces when each capsule transitions from the vacuum tube to the atmosphere. A SPESIF 2010 presentation stated that Generation 1 could be completed by the year 2020 or later if funding began in 2010, and Generation 2 by 2030 or later.

🔗 Food and drink 🔗 United Kingdom

A toast sandwich is a sandwich made with two slices of bread in which the filling is a thin slice of toasted bread, which can be heavily buttered. An 1861 recipe says to add salt and pepper to taste.

🔗 Databases

Third normal form (3NF) is a database schema design approach for relational databases which uses normalizing principles to reduce the duplication of data, avoid data anomalies, ensure referential integrity, and simplify data management. It was defined in 1971 by Edgar F. Codd, an English computer scientist who invented the relational model for database management.

A database relation (e.g. a database table) is said to meet third normal form standards if all the attributes (e.g. database columns) are functionally dependent on solely the primary key. Codd defined this as a relation in second normal form where all non-prime attributes depend only on the candidate keys and do not have a transitive dependency on another key.

A hypothetical example of a failure to meet third normal form would be a hospital database having a table of patients which included a column for the telephone number of their doctor. The phone number is dependent on the doctor, rather than the patient, thus would be better stored in a table of doctors. The negative outcome of such a design is that a doctor's number will be duplicated in the database if they have multiple patients, thus increasing both the chance of input error and the cost and risk of updating that number should it change (compared to a third normal form-compliant data model that only stores a doctor's number once on a doctor table).

Codd later realized that 3NF did not eliminate all undesirable data anomalies and developed a stronger version to address this in 1974, known as Boyce–Codd normal form.

🔗 Game theory

The Price of Anarchy (PoA) is a concept in economics and game theory that measures how the efficiency of a system degrades due to selfish behavior of its agents. It is a general notion that can be extended to diverse systems and notions of efficiency. For example, consider the system of transportation of a city and many agents trying to go from some initial location to a destination. Let efficiency in this case mean the average time for an agent to reach the destination. In the 'centralized' solution, a central authority can tell each agent which path to take in order to minimize the average travel time. In the 'decentralized' version, each agent chooses its own path. The Price of Anarchy measures the ratio between average travel time in the two cases.

Usually the system is modeled as a game and the efficiency is some function of the outcomes (e.g. maximum delay in a network, congestion in a transportation system, social welfare in an auction, ...). Different concepts of equilibrium can be used to model the selfish behavior of the agents, among which the most common is the Nash equilibrium. Different flavors of Nash equilibrium lead to variations of the notion of Price of Anarchy as Pure Price of Anarchy (for deterministic equilibria), Mixed Price of Anarchy (for randomized equilibria), and Bayes–Nash Price of Anarchy (for games with incomplete information). Solution concepts other than Nash equilibrium lead to variations such as the Price of Sinking.

The term Price of Anarchy was first used by Elias Koutsoupias and Christos Papadimitriou, but the idea of measuring inefficiency of equilibrium is older. The concept in its current form was designed to be the analogue of the 'approximation ratio' in an approximation algorithm or the 'competitive ratio' in an online algorithm. This is in the context of the current trend of analyzing games using algorithmic lenses (algorithmic game theory).

🔗 Norse history and culture 🔗 Ancient Germanic studies

The sequence alu (ᚨᛚᚢ) is found in numerous Elder Futhark runic inscriptions of Germanic Iron Age Scandinavia (and more rarely in early Anglo-Saxon England) between the 3rd and the 8th century. The word usually appears either alone (such as on the Elgesem runestone) or as part of an apparent formula (such as on the Lindholm "amulet" (DR 261) from Scania, Sweden). The symbols represent the runes Ansuz, Laguz, and Uruz. The origin and meaning of the word are matters of dispute, though a general agreement exists among scholars that the word represents an instance of historical runic magic or is a metaphor (or metonym) for it. It is the most common of the early runic charm words.

The word disappears from runic inscriptions shortly after Migration Period, even before the Christianization of Scandinavia. It may have lived on beyond this period with an increasing association with ale, appearing in stanzas 7 and 19 of the Old Norse poem Sigrdrífumál, compiled in the 13th century Poetic Edda, where knowledge of invocative "ale runes" (Old Norse ölrúnar) is imparted by the Valkyrie Sigrdrífa. Theories have been suggested that the unique term ealuscerwen (possibly "pouring away of alu"), used to describe grief or terror in the epic poem Beowulf, recorded around the 9th to 11th century, may be directly related.

🔗 Architecture

Atlantropa, also referred to as Panropa, was a gigantic engineering and colonisation idea devised by the German architect Herman Sörgel in the 1920s and promoted by him until his death in 1952. Its central feature was a hydroelectric dam to be built across the Strait of Gibraltar, which would have provided enormous amounts of hydroelectricity and would have led to the lowering of the surface of the Mediterranean Sea by up to 200 metres (660 ft), opening up large new lands for settlement, for example in the Adriatic Sea. The project proposed four additional major dams as well:

• Across the Dardanelles to hold back the Black Sea
• Between Sicily and Tunisia to provide a roadway and further lower the inner Mediterranean
• On the Congo River below its Kwah River tributary to refill the Mega-Chad basin around Lake Chad providing fresh water to irrigate the Sahara and creating a shipping lane to the interior of Africa
• Suez Canal extension and locks to maintain Red Sea connection

Sörgel saw his scheme, projected to take over a century, as a peaceful European-wide alternative to the Lebensraum concepts that later became one of the stated reasons for Nazi Germany's conquest of new territories. Atlantropa would provide land and food, employment, electric power, and most of all, a new vision for Europe and neighbouring Africa.

The Atlantropa movement, through its several decades, was characterised by four constants:

• Pacifism, in its promises of using technology in a peaceful way;
• Pan-European sentiment, seeing the project as a way to unite a war-torn Europe;
• Eurocentric attitudes to Africa (which was to become united with Europe into "Atlantropa" or Eurafrica), and
• Neo-colonial geopolitics, which saw the world divided into three blocs—America, Asia, and Atlantropa.

Active support was limited to architects and planners from Germany and a number of other primarily northern European countries. Critics derided it for various faults, ranging from lack of any cooperation of Mediterranean countries in the planning to the impacts it would have had on the historic coastal communities left stranded inland when the sea receded. The project reached great popularity in the late 1920s to the early 1930s, and for a short period again, in the late 1940s to the early 1950s, but soon disappeared from general discourse again after Sörgel's death.