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🔗 History 🔗 Ancient Near East 🔗 Business 🔗 Iraq

The complaint tablet to Ea-nasir is a clay tablet from ancient Babylon written c. 1750 BC. It is a complaint to a merchant named Ea-Nasir from a customer named Nanni. Written in cuneiform, it is considered to be the oldest known written complaint. It is currently kept in the British Museum.

Ea-Nasir travelled to the Persian Gulf to buy copper and return to sell it in Mesopotamia. On one particular occasion, he had agreed to sell copper ingots to Nanni. Nanni sent his servant with the money to complete the transaction. The copper was sub-standard and not accepted. In response, Nanni created the cuneiform letter for delivery to Ea-nasir. Inscribed on it is a complaint to Ea-nasir about a copper ore delivery of the incorrect grade, and issues with another delivery. He also complained that his servant (who handled the transaction) had been treated rudely. He stated that, at the time of writing, he had not accepted the copper but had paid the money.

The tablet is 11.6 centimetres (4.6 in) high, 5 centimetres (2.0 in) wide, 2.6 centimetres (1.0 in) thick, and slightly damaged. Translated from Akkadian, it reads:

Tell Ea-nasir: Nanni sends the following message:

When you came, you said to me as follows : "I will give Gimil-Sin (when he comes) fine quality copper ingots." You left then but you did not do what you promised me. You put ingots which were not good before my messenger (Sit-Sin) and said: "If you want to take them, take them; if you do not want to take them, go away!"

What do you take me for, that you treat somebody like me with such contempt? I have sent as messengers gentlemen like ourselves to collect the bag with my money (deposited with you) but you have treated me with contempt by sending them back to me empty-handed several times, and that through enemy territory. Is there anyone among the merchants who trade with Telmun who has treated me in this way? You alone treat my messenger with contempt! On account of that one (trifling) mina of silver which I owe(?) you, you feel free to speak in such a way, while I have given to the palace on your behalf 1,080 pounds of copper, and Šumi-abum has likewise given 1,080 pounds of copper, apart from what we both have had written on a sealed tablet to be kept in the temple of Shamash.

How have you treated me for that copper? You have withheld my money bag from me in enemy territory; it is now up to you to restore (my money) to me in full.

Take cognizance that (from now on) I will not accept here any copper from you that is not of fine quality. I shall (from now on) select and take the ingots individually in my own yard, and I shall exercise against you my right of rejection because you have treated me with contempt.

The tablet was acquired by the British Museum in 1953. It was originally found in the ruins of Ur.

🔗 Mathematics

Gödel's completeness theorem is a fundamental theorem in mathematical logic that establishes a correspondence between semantic truth and syntactic provability in first-order logic. It makes a close link between model theory that deals with what is true in different models, and proof theory that studies what can be formally proven in particular formal systems.

It was first proved by Kurt Gödel in 1929. It was then simplified in 1947, when Leon Henkin observed in his Ph.D. thesis that the hard part of the proof can be presented as the Model Existence Theorem (published in 1949). Henkin's proof was simplified by Gisbert Hasenjaeger in 1953.

🔗 Aviation 🔗 Marketing & Advertising 🔗 United Kingdom 🔗 Guild of Copy Editors 🔗 Retailing 🔗 Home Living

The Hoover free flights promotion was a marketing promotion run by the British division of the Hoover Company in late 1992. The promotion, aiming to boost sales during the global recession of the early 1990s, offered two complimentary round-trip plane tickets to the United States, worth about £600, to any customer purchasing at least £100 in Hoover products. Hoover had been experiencing dwindling sales as a result of the economic downturn and a sharp increase in competing brands. Hoover was counting on most customers spending more than £100, as well as being deterred from completing the difficult application process, and not meeting its exact terms.

Consumer response was much higher than the company anticipated, with many customers buying the minimum £100 of Hoover products to qualify. It was perceived as two US flights for just £100 with a free vacuum cleaner included. The resulting demand was disastrous for the 84-year-old company. Hoover cancelled the ticket promotion after consumers had already bought the products and filled in forms applying for millions of pounds' worth of tickets. Reneging on the offer resulted in protests and legal action from customers who failed to receive the tickets they had been promised. The campaign was a financial disaster for the company and led to the loss of Hoover's Royal Warrant after the airing of a 2004 BBC documentary. The European branch of the company was eventually sold to one of its competitors, Candy, having never recovered from the losses, the promotion and the subsequent scandal.

🔗 United States/U.S. Government 🔗 United States 🔗 Biography 🔗 International relations 🔗 Human rights 🔗 Mass surveillance 🔗 Espionage 🔗 United States/North Carolina

Edward Joseph Snowden (born June 21, 1983) is an American whistleblower who copied and leaked highly classified information from the National Security Agency (NSA) in 2013 when he was a Central Intelligence Agency (CIA) employee and subcontractor. His disclosures revealed numerous global surveillance programs, many run by the NSA and the Five Eyes Intelligence Alliance with the cooperation of telecommunication companies and European governments, and prompted a cultural discussion about national security and individual privacy.

In 2013, Snowden was hired by an NSA contractor, Booz Allen Hamilton, after previous employment with Dell and the CIA. Snowden says he gradually became disillusioned with the programs with which he was involved and that he tried to raise his ethical concerns through internal channels but was ignored. On May 20, 2013, Snowden flew to Hong Kong after leaving his job at an NSA facility in Hawaii, and in early June he revealed thousands of classified NSA documents to journalists Glenn Greenwald, Laura Poitras, and Ewen MacAskill. Snowden came to international attention after stories based on the material appeared in The Guardian and The Washington Post. Further disclosures were made by other publications including Der Spiegel and The New York Times.

On June 21, 2013, the United States Department of Justice unsealed charges against Snowden of two counts of violating the Espionage Act of 1917 and theft of government property, following which the Department of State revoked his passport. Two days later, he flew into Moscow's Sheremetyevo Airport, where Russian authorities noted that his U.S. passport had been cancelled, and he was restricted to the airport terminal for over one month. Russia later granted Snowden the right of asylum with an initial visa for residence for one year, and repeated extensions have permitted him to stay at least until 2020. In early 2016, he became the president of the Freedom of the Press Foundation, a San Francisco-based organization that states its purpose is to protect journalists from hacking and government surveillance.

On September 17, 2019, his memoir Permanent Record was published. On the first day of publication, the U.S. Department of Justice filed a civil lawsuit against Snowden over publication of his memoir, alleging he had breached nondisclosure agreements signed with the U.S. federal government. Former The Guardian national security reporter Ewen MacAskill called the civil lawsuit a "huge mistake", noting that the "UK ban of Spycatcher 30 years ago created huge demand". The memoir was listed as no. 1 on Amazon's bestseller list that same day. In an interview with Amy Goodman on Democracy Now! on September 26, 2019, Snowden clarified he considers himself a "whistleblower" as opposed to a "leaker" as he considers "a leaker only distributes information for personal gain".

🔗 Computer science

Pearson hashing is a hash function designed for fast execution on processors with 8-bit registers. Given an input consisting of any number of bytes, it produces as output a single byte that is strongly dependent on every byte of the input. Its implementation requires only a few instructions, plus a 256-byte lookup table containing a permutation of the values 0 through 255.

This hash function is a CBC-MAC that uses an 8-bit substitution cipher implemented via the substitution table. An 8-bit cipher has negligible cryptographic security, so the Pearson hash function is not cryptographically strong, but it is useful for implementing hash tables or as a data integrity check code, for which purposes it offers these benefits:

• It is extremely simple.
• It executes quickly on resource-limited processors.
• There is no simple class of inputs for which collisions (identical outputs) are especially likely.
• Given a small, privileged set of inputs (e.g., reserved words for a compiler), the permutation table can be adjusted so that those inputs yield distinct hash values, producing what is called a perfect hash function.
• Two input strings differing by exactly one character never collide. E.g., applying the algorithm on the strings ABC and AEC will never produce the same value.

One of its drawbacks when compared with other hashing algorithms designed for 8-bit processors is the suggested 256 byte lookup table, which can be prohibitively large for a small microcontroller with a program memory size on the order of hundreds of bytes. A workaround to this is to use a simple permutation function instead of a table stored in program memory. However, using a too simple function, such as T[i] = 255-i, partly defeats the usability as a hash function as anagrams will result in the same hash value; using a too complex function, on the other hand, will affect speed negatively. Using a function rather than a table also allows extending the block size. Such functions naturally have to be bijective, like their table variants.

The algorithm can be described by the following pseudocode, which computes the hash of message C using the permutation table T:

algorithm pearson hashing is
    h := 0

    for each c in C loop
        h := T[ h xor c ]
    end loop

    return h

The hash variable (h) may be initialized differently, e.g. to the length of the data (C) modulo 256; this particular choice is used in the Python implementation example below.

🔗 Internet culture

The Valeriepieris circle is a South China Sea-centered circular region on the world map that is about 4,000 kilometers (2,500 mi) in radius and contains more than half the world’s population. It was named after the Reddit username of Ken Myers, a Texas ESL teacher who first drew attention to the phenomenon in 2013. The map became a meme and was featured in numerous forms of media.

In 2015, the circle was tested by Danny Quah, who verified the claim but moved the circle slightly to exclude most of Japan, and used a globe model rather than a map projection as well as more specific calculations. He calculated that, as of 2015, half of the world's population lived within a 3,300-kilometer (2,050 mi) radius of the city of Mong Khet in Myanmar.

The most common visual of the circle, originally used by Myers and also featured by io9 and Tech in Asia, used the Winkel tripel projection.

🔗 Computing 🔗 Computer Security 🔗 Computer Security/Computing 🔗 Computing/Software 🔗 Cryptography 🔗 Cryptography/Computer science

Pretty Good Privacy (PGP) is an encryption program that provides cryptographic privacy and authentication for data communication. PGP is used for signing, encrypting, and decrypting texts, e-mails, files, directories, and whole disk partitions and to increase the security of e-mail communications. Phil Zimmermann developed PGP in 1991.

PGP and similar software follow the OpenPGP, an open standard of PGP encryption software, standard (RFC 4880) for encrypting and decrypting data.

🔗 Brands 🔗 Automobiles

The Isetta is an Italian-designed microcar built under license in a number of different countries, including Argentina, Spain, Belgium, France, Brazil, Germany, and the United Kingdom. Because of its egg shape and bubble-like windows, it became known as a bubble car, a name also given to other similar vehicles.

In 1955, the BMW Isetta became the world's first mass-production car to achieve a fuel consumption of 3 L/100 km (94 mpg_‑imp; 78 mpg_‑US). It was the top-selling single-cylinder car in the world, with 161,728 units sold.

Initially manufactured by the Italian firm Iso SpA, the name Isetta is the Italian diminutive form of Iso, meaning "little Iso".

🔗 Psychology

The surprisingly popular answer is a wisdom of the crowd technique that taps into the expert minority opinion within a crowd. For a given question, a group is asked both "What do you think the right answer is?" and "What do you think the popular answer will be?" The answer that maximizes the average difference between the "right" answer and the "popular" answer is the "surprisingly popular" answer.

🔗 Military history 🔗 Disaster management 🔗 Death 🔗 China/Chinese history 🔗 China 🔗 Astronomy 🔗 Geology 🔗 Military history/Asian military history 🔗 Geology/Meteorites 🔗 Military history/Chinese military history 🔗 Explosives 🔗 Astronomy/Solar System

The Wanggongchang Explosion (Chinese: 王恭廠大爆炸), also known as the Great Tianqi Explosion (天啟大爆炸), Wanggongchang Calamity (王恭廠之變) or Beijing Explosive Incident in Late Ming (晚明北京爆炸事件), was an unexplained catastrophic explosion that occurred on May 30 of the Chinese calendar in 1626 AD during the late reign of Tianqi Emperor, at the heavily populated Ming China capital Beijing, and had reportedly killed around 20,000 people. The nature of the explosion is still unclear to this day, as it is estimated to have released energy equivalent to about 10-20 kiloton of TNT, similar to that of the Hiroshima bombing.