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🔗 Biography

Ward Christensen (born 1945 in West Bend, Wisconsin, United States) was the co-founder of the CBBS bulletin board, the first bulletin board system (BBS) ever brought online. Christensen, along with partner Randy Suess, members of the Chicago Area Computer Hobbyists' Exchange (CACHE), started development during a blizzard in Chicago, Illinois, and officially established CBBS four weeks later, on February 16, 1978. CACHE members frequently shared programs and had long been discussing some form of file transfer, and the two used the downtime during the blizzard to implement it.

Christensen was noted for building software tools for his needs. He wrote a cassette-based operating system before floppies and hard disks were common. When he lost track of the source code for some programs, he wrote ReSource, an iterative disassembler for the Intel 8080, to help him regenerate the source code. When he needed to send files to Randy Suess, he wrote XMODEM.

Jerry Pournelle wrote in 1983 of a collection of CP/M public-domain software that "probably 50 percent of the really good programs were written by Ward Christensen, a public benefactor." Christensen received two 1992 Dvorak Awards for Excellence in Telecommunications, one with Randy Suess for developing the first BBS, and a lifetime achievement award "for outstanding contributions to PC telecommunications." In 1993, he received the Pioneer Award from the Electronic Frontier Foundation.

Christensen worked at IBM from 1968 until his retirement in 2012. His last position with IBM was field technical sales specialist.

In May 2005, Christensen and Suess were both featured in BBS: The Documentary.

🔗 Mathematics

In mathematics, tetration (or hyper-4) is an operation based on iterated, or repeated, exponentiation. It is the next hyperoperation after exponentiation, but before pentation. The word was coined by Reuben Louis Goodstein from tetra- (four) and iteration.

Under the definition as repeated exponentiation, the notation ${\displaystyle {^{n}a}}$ means ${\displaystyle {a^{a^{\cdot ^{\cdot ^{a}}}}}}$, where n copies of a are iterated via exponentiation, right-to-left, I.e. the application of exponentiation ${\displaystyle n-1}$ times. n is called the "height" of the function, while a is called the "base," analogous to exponentiation. It would be read as "the nth tetration of a".

Tetration is also defined recursively as

${\displaystyle {^{n}a}:={\begin{cases}1&{\text{if }}n=0\\a^{\left(^{(n-1)}a\right)}&{\text{if }}n>0\end{cases}}}$,

allowing for attempts to extend tetration to non-natural numbers such as real and complex numbers.

The two inverses of tetration are called the super-root and the super-logarithm, analogous to the nth root and the logarithmic functions. None of the three functions are elementary.

Tetration is used for the notation of very large numbers.

🔗 Urban studies and planning

Marchetti's constant is the average time spent by a person for commuting each day, which is approximately one hour. It is named after Italian physicist Cesare Marchetti, though Marchetti himself attributed the "one hour" finding to transportation analyst and engineer Yacov Zahavi. Marchetti posits that although forms of urban planning and transport may change, and although some live in villages and others in cities, people gradually adjust their lives to their conditions (including location of their homes relative to their workplace) such that the average travel time stays approximately constant. Ever since Neolithic times, people have kept the average time spent per day for travel the same, even though the distance may increase due to the advancements in the means of transportation. In his 1934 book Technics and Civilization, Lewis Mumford attributes this observation to Bertrand Russell:

Mr. Bertrand Russell has noted that each improvement in locomotion has increased the area over which people are compelled to move: so that a person who would have had to spend half an hour to walk to work a century ago must still spend half an hour to reach his destination, because the contrivance that would have enabled him to save time had he remained in his original situation now—by driving him to a more distant residential area—effectually cancels out the gain.

A related concept is that of Zahavi, who also noticed that people seem to have a constant "travel time budget", that is, "a stable daily amount of time that people make available for travel." David Metz, former chief scientist at the Department of Transport, UK, cites data of average travel time in Britain drawn from the British National Travel Survey in support of Marchetti's and Zahavi's conclusions. The work casts doubt on the contention that investment in infrastructure saves travel time. Instead, it appears from Metz's figures that people invest travel time saved in travelling a longer distance, a particular example of Jevons paradox described by the Lewis–Mogridge position. Because of the constancy of travel times as well as induced travel, Robert Cervero has argued that the World Bank and other international aid agencies evaluate transportation investment proposals in developing and rapidly motorizing cities less on the basis of potential travel-time savings and more on the accessibility benefits they confer.

🔗 Spirits 🔗 Chicago

Jeppson's Malört is an American brand of bäsk liqueur, a type of brännvin flavored with anise or wormwood. Malört was introduced in Chicago in the 1930s and was long produced by the Carl Jeppson Company. In 2018, as its last employee was retiring, the brand and company name were sold to CH Distillery of Chicago's Pilsen neighborhood. Jeppson's Malört is named after Carl Jeppson, a Swedish immigrant who first distilled and popularized the liquor in Chicago. Malört (literally moth herb) is the Swedish word for wormwood, which is the key ingredient in bäsk. Malört is extremely low in thujone, a chemical once prevalent in absinthe and similar drinks.

Known for its extremely bitter taste, Malört has been described as "infamous" and "the worst booze ever". It can be found in some Chicago-area bars and liquor stores, and is growing in popularity, with sales of Malört shots increasing from 0.4 million in 2007 to 7.9 million in 2022. However, it is rare to find elsewhere in the United States.

🔗 Military history 🔗 Fashion

A necktie, or simply a tie, is a long piece of cloth, worn, usually by men, for decorative purposes around the neck, resting under the shirt collar and knotted at the throat.

Variants include the ascot, bow, bolo, zipper, cravat, and knit. The modern necktie, ascot, and bow tie are descended from the cravat. Neckties are generally unsized, but may be available in a longer size. In some cultures men and boys wear neckties as part of regular office attire or formal wear. Some women wear them as well but usually not as often as men. Neckties can also be worn as part of a uniform (e.g. military, school, waitstaff), whereas some choose to wear them as everyday clothing attire. Neckties are traditionally worn with the top shirt button fastened, and the tie knot resting between the collar points.

🔗 United States 🔗 Organizations

An important part of the counterculture of the 1970s, Project One, sometimes described as a technological commune, was an intentional community in San Francisco, California, U.S. Located at 1380 Howard St. in an 84,000 square foot warehouse, formerly an abandoned candy factory, the community functioned from 1970 to 1980 and was the first "warehouse community" in San Francisco. Occupied by a shifting mix of students, craftspeople, artisans, sculptors, filmmakers, and technologists, Project One was anchored by a number of organizations.

The community had no formal organizational structure. Decisions were made through a voluntary weekly meeting of members who made decisions based on a consensus of those present.

Project One was initiated by architect Ralph Scott, a former student of Buckminster Fuller, and rapidly became an interdisciplinary learning environment. Central to the concept was Symbas Alternative High School, founded by Scott and located in a large, high-ceiling space on the first floor. Many of these resident non-profit organizations and small businesses were brought in to serve as resources for the students, who were also members of the larger community. Students found mentors who offered skills training and the opportunities to practice new skills. See also community of place.

🔗 Civil engineering

A green wave occurs when a series of traffic lights (usually three or more) are coordinated to allow continuous traffic flow over several intersections in one main direction.

Any vehicle travelling along with the green wave (at an approximate speed decided upon by the traffic engineers) will see a progressive cascade of green lights, and not have to stop at intersections. This allows higher traffic loads, and reduces noise and energy use (because less acceleration and braking is needed). In practical use, only a group of cars (known as a "platoon", the size of which is defined by the signal times) can use the green wave before the time band is interrupted to give way to other traffic flows.

The coordination of the signals is sometimes done dynamically, according to sensor data of currently existing traffic flows - otherwise it is done statically, by the use of timers. Under certain circumstances, green waves can be interwoven with each other, but this increases their complexity and reduces usability, so in conventional set-ups only the roads and directions with the heaviest loads get this preferential treatment.

In 2011, a study modeled the implementation of green waves during the night in a busy Manchester suburb (Chorlton-cum-Hardy) using S-Paramics microsimulation and the AIRE emissions module. The results showed using green wave signal setups on a network have the potential to:

• Reduce CO₂, NO_x and PM₁₀ emissions from traffic.
• Reduce fuel consumption of vehicles.
• Be used on roads that intersect with other green waves.
• Reduce the time cars wait at side roads.
• Give pedestrians more time to cross at crossings and help them to cross streets as vehicles travel in platoons
• Control the speed of traffic in urban areas.
• Reduce component wear of vehicles and indirect energy consumption through their manufacture

A green wave in both directions may be possible with different speed recommendations for each direction, otherwise traffic coming from one direction may reach the traffic light faster than from the other direction if the distance from the previous traffic light is not mathematically a multiple of the opposite direction. Alternatively a dual carriageway may be suitable for green waves in both directions if there is sufficient space in the central reservation to allow pedestrians to wait and separate pedestrian crossing stages for each side of the road.

Green waves are sometimes used to facilitate bicycle traffic. Copenhagen, Amsterdam, San Francisco, and other cities may synchronize traffic signals to provide a green light for a flow of cyclists. On San Francisco's Valencia Street, the signals were retimed in early 2009 to provide a green wave in both directions, possibly the first street in the world with a two-way green wave for cyclists. In Copenhagen, a green wave on the arterial street Nørrebrogade facilitates 30,000 cyclists to maintain a 12 mph (19.3 km/h) speed for 2.5 kilometers. In Amsterdam, cyclists riding at a speed of 15 to 18 km/h will be able to travel without being stopped by a red signal. Tests show that public transport can benefit as well and cars may travel slightly slower.

In Vienna, Austria a stretch of cycle path on Lassellestrasse in the 2nd district has a display that tells cyclists their speed and the speed they must maintain to make the next green light.

Frederiksberg, a part of Copenhagen, the capital of Denmark, has implemented a green wave for emergency vehicles to improve the public services.

In the UK, in 2009, it was revealed that the Department for Transport had previously discouraged green waves as they reduced fuel usage, and thus less revenue was raised from fuel taxes. Despite this government Webtag documents were only updated in 2011. It is still unclear if the economic appraisal software used to apply these guidelines has also been updated and if the new guidelines are being applied to new projects.

In a more limited sense, the term Green wave has also been applied to railroad travel. For several years starting in the 1960s, the German Federal Railway maintained an advertising campaign featuring the slogan garantiert grüne Welle (Guaranteed Green Wave), which communicated the notion of speed, limited delays and open track blocks to potential customers choosing between train and automobile travel, and was featured prominently in promotional materials ranging from posters to radio jingles.

🔗 Trains 🔗 Trains/Monorail

The Wuppertaler Schwebebahn (Wuppertal Suspension Railway) is a suspension railway in Wuppertal, Germany.

Its full name is Anlage einer elektrischen Hochbahn (Schwebebahn), System Eugen Langen. ("Electric Elevated Railway (Suspension Railway) Installation, Eugen Langen System") It is the oldest electric elevated railway with hanging cars in the world and is a unique system.

Designed by Eugen Langen to sell to the city of Berlin, the installation with elevated stations was built in Barmen, Elberfeld and Vohwinkel between 1897 and 1903; the first track opened in 1901. The Schwebebahn is still in use today as a normal means of local public transport, moving 25 million passengers annually (2008).

The Schwebebahn runs along a route of 13.3 kilometres (8.3 mi), at a height of about 12 metres (39 ft) above the River Wupper between Oberbarmen and Sonnborner Straße (10 kilometres or 6.2 miles) and about 8 metres (26 ft) above the valley road between Sonnborner Straße and Vohwinkel (3.3 kilometres or 2.1 miles). At one point the railway crosses the A46 motorway. The entire trip takes about 30 minutes. The Schwebebahn operates within the VRR transport association and accepts tickets issued by the VRR companies.

Due to an accident in November 2018, the Schwebebahn was closed down for nearly nine months. It re-opened on 1 August 2019.

🔗 United States/U.S. Government 🔗 United States 🔗 International relations 🔗 Law 🔗 Law Enforcement 🔗 United States Public Policy 🔗 Pirate Politics 🔗 International relations/International law 🔗 United States/U.S. Public Policy 🔗 Trade

The Anti-Counterfeiting Trade Agreement (ACTA) was a proposed multilateral treaty for the purpose of establishing international standards for intellectual property rights enforcement. The agreement aims to establish an international legal framework for targeting counterfeit goods, generic medicines and copyright infringement on the Internet, and would create a new governing body outside existing forums, such as the World Trade Organization, the World Intellectual Property Organization, and the United Nations.

The agreement was signed in October 2011 by Australia, Canada, Japan, Morocco, New Zealand, Singapore, South Korea, and the United States. In 2012, Mexico, the European Union and 22 countries that are member states of the European Union signed as well. One signatory (Japan) has ratified (formally approved) the agreement, which would come into force in countries that ratified it after ratification by six countries.

Industrial groups with interests in copyright, trademarks and other types of intellectual property said that ACTA was a response to "the increase in global trade of counterfeit goods and pirated copyright protected works". Organizations such as the Motion Picture Association of America and International Trademark Association are understood to have had a significant influence over the ACTA agenda.

Organisations representing citizens and non-governmental interests argued that ACTA could infringe fundamental rights including freedom of expression and privacy. ACTA has also been criticised by Doctors Without Borders for endangering access to medicines in developing countries. The nature of negotiations was criticized as secretive and has excluded non-governmental organization, developing countries and the general public from the agreement's negotiation process and it has been described as policy laundering by critics including the Electronic Frontier Foundation and the Entertainment Consumers Association.

The signature of the EU and many of its member states resulted in widespread protests across Europe. European Parliament rapporteur Kader Arif resigned. His replacement, British MEP David Martin, recommended that the Parliament should reject ACTA, stating: "The intended benefits of this international agreement are far outweighed by the potential threats to civil liberties". On 4 July 2012, the European Parliament declined its consent, effectively rejecting it, 478 votes to 39, with 165 abstentions.

🔗 Chess

The Immortal Game was a chess game played by Adolf Anderssen and Lionel Kieseritzky on 21 June 1851 in London, during a break of the first international tournament. The bold sacrifices made by Anderssen to secure victory have made it one of the most famous chess games of all time. Anderssen gave up both rooks and a bishop, then his queen, checkmating his opponent with his three remaining minor pieces. In 1996, Bill Hartston called the game an achievement "perhaps unparalleled in chess literature".