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๐ SCOOP: Simple Concurrent Object Oriented Programming
SCOOP (Simple Concurrent Object Oriented Programming) is a concurrency model designed for the Eiffel programming language, conceived by Eiffel's creator and designer, Bertrand Meyer.
SCOOP defines a way for an object oriented program to be written without the concept of threads, locks, or other typical multiprogramming methods. This allows the compiler or runtime environment to optimize the amount of concurrency as well as eliminate typical design flaws such as deadlock.
The model was first designed in the early 1990s and published in 1993 in the Communications of the ACM An updated version was described in chapter 30 of the book Object-Oriented Software Construction. A prototype implementation was developed in 1995 by Eiffel Software. An article by Compton and Walker provides an overview of SCOOP and describes another early implementation. Nienaltowski, Arslan and Meyer have published a description of the model as of 2003. Work on SCOOP proceeded at the Chair of Software Engineering at ETH Zurich. SCOOP became available as a standard part of EiffelStudio early in 2011.
๐ Nicolas Bourbaki: The Greatest Mathematician That Never Existed
Nicolas Bourbaki (French pronunciation:ย โ[nikษla buสbaki]) is the collective pseudonym of a group of mathematicians, predominantly French alumni of the รcole normale supรฉrieure (ENS). Founded in 1934โ1935, the Bourbaki group originally intended to prepare a new textbook in analysis. Over time the project became much more ambitious, growing into a large series of textbooks published under the Bourbaki name, meant to treat modern pure mathematics. The series is known collectively as the รlรฉments de mathรฉmatique (Elements of Mathematics), the group's central work. Topics treated in the series include set theory, abstract algebra, topology, analysis, Lie groups and Lie algebras.
Bourbaki was founded in response to the effects of the First World War which caused the death of a generation of French mathematicians; as a result, young university instructors were forced to use dated texts. While teaching at the University of Strasbourg, Henri Cartan complained to his colleague Andrรฉ Weil of the inadequacy of available course material, which prompted Weil to propose a meeting with others in Paris to collectively write a modern analysis textbook. The group's core founders were Cartan, Claude Chevalley, Jean Delsarte, Jean Dieudonnรฉ and Weil; others participated briefly during the group's early years, and membership has changed gradually over time. Although former members openly discuss their past involvement with the group, Bourbaki has a custom of keeping its current membership secret.
The group's namesake derives from the 19th century French general Charles-Denis Bourbaki, who had a career of successful military campaigns before suffering a dramatic loss in the Franco-Prussian War. The name was therefore familiar to early 20th century French students. Weil remembered an ENS student prank in which an upperclassman posed as a professor and presented a "theorem of Bourbaki"; the name was later adopted.
The Bourbaki group holds regular private conferences for the purpose of drafting and expanding the รlรฉments. Topics are assigned to subcommittees, drafts are debated, and unanimous agreement is required before a text is deemed fit for publication. Although slow and labor-intensive, the process results in a work which meets the group's standards for rigour and generality. The group is also associated with the Sรฉminaire Bourbaki, a regular series of lectures presented by members and non-members of the group, also published and disseminated as written documents. Bourbaki maintains an office at the ENS.
Nicolas Bourbaki was influential in 20th century mathematics, particularly during the middle of the century when volumes of the รlรฉments appeared frequently. The group is noted among mathematicians for its rigorous presentation and for introducing the notion of a mathematical structure, an idea related to the broader, interdisciplinary concept of structuralism. Bourbaki's work informed the New Math, a trend in elementary math education during the 1960s. Although the group remains active, its influence is considered to have declined due to infrequent publication of new volumes of the รlรฉments. However the collective's most recent publication appeared in 2016, treating algebraic topology.
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- "Nicolas Bourbaki" | 2024-03-14 | 64 Upvotes 49 Comments
- "Nicolas Bourbaki: The Greatest Mathematician That Never Existed" | 2020-07-20 | 19 Upvotes 5 Comments
๐ Wuppertal Suspension Railway
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 (8.3ย mi), at a height of about 12 metres (39ย ft) above the River Wupper between Oberbarmen and Sonnborner Straรe (10 kilometres or 6.2 miles) and about 8 metres (26ย ft) above the valley road between Sonnborner Straรe 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.
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- "Wuppertal Suspension Railway" | 2016-03-05 | 62 Upvotes 20 Comments
๐ Mozilla made $436M from search deals in 2018
The Mozilla Corporation (stylized as moz://a) is a wholly owned subsidiary of the Mozilla Foundation that coordinates and integrates the development of Internet-related applications such as the Firefox web browser, by a global community of open-source developers, some of whom are employed by the corporation itself. The corporation also distributes and promotes these products. Unlike the non-profit Mozilla Foundation, and the Mozilla open source project, founded by the now defunct Netscape Communications Corporation, the Mozilla Corporation is a taxable entity. The Mozilla Corporation reinvests all of its profits back into the Mozilla projects. The Mozilla Corporation's stated aim is to work towards the Mozilla Foundation's public benefit to "promote choice and innovation on the Internet."
A MozillaZine article explained:
The Mozilla Foundation will ultimately control the activities of the Mozilla Corporation and will retain its 100 percent ownership of the new subsidiary. Any profits made by the Mozilla Corporation will be invested back into the Mozilla project. There will be no shareholders, no stock options will be issued and no dividends will be paid. The Mozilla Corporation will not be floating on the stock market and it will be impossible for any company to take over or buy a stake in the subsidiary. The Mozilla Foundation will continue to own the Mozilla trademarks and other intellectual property and will license them to the Mozilla Corporation. The Foundation will also continue to govern the source code repository and control who is allowed to check in.
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- "Mozilla made $436M from search deals in 2018" | 2020-08-12 | 32 Upvotes 3 Comments
๐ Deep Crack
In cryptography, the EFF DES cracker (nicknamed "Deep Crack") is a machine built by the Electronic Frontier Foundation (EFF) in 1998, to perform a brute force search of the Data Encryption Standard (DES) cipher's key space โ that is, to decrypt an encrypted message by trying every possible key. The aim in doing this was to prove that the key size of DES was not sufficient to be secure.
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- "Deep Crack" | 2009-04-24 | 23 Upvotes 6 Comments
๐ Wardenclyffe Tower a.k.a. the Tesla Tower
Wardenclyffe Tower (1901โ1917), also known as the Tesla Tower, was an early experimental wireless transmission station designed and built by Nikola Tesla in Shoreham, New York in 1901โ1902. Tesla intended to transmit messages, telephony and even facsimile images across the Atlantic to England and to ships at sea based on his theories of using the Earth to conduct the signals. His decision to scale up the facility and add his ideas of wireless power transmission to better compete with Guglielmo Marconi's radio based telegraph system was met with refusal to fund the changes by the project's primary backer, financier J. P. Morgan. Additional investment could not be found, and the project was abandoned in 1906, never to become operational.
In an attempt to satisfy Tesla's debts, the tower was demolished for scrap in 1917 and the property taken in foreclosure in 1922. For 50 years, Wardenclyffe was a processing facility producing photography supplies. Many buildings were added to the site and the land it occupies has been trimmed down to 16 acres (6.5ย ha) but the original, 94 by 94ย ft (29 by 29ย m), brick building designed by Stanford White remains standing to this day.
In the 1980s and 2000s, hazardous waste from the photographic era was cleaned up, and the site was sold and cleared for new development. A grassroots campaign to save the site succeeded in purchasing the property in 2013, with plans to build a future museum dedicated to Nikola Tesla. In 2018 the property was listed on the National Register of Historic Places.
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- "Wardenclyffe Tower a.k.a. the Tesla Tower" | 2011-01-28 | 10 Upvotes 1 Comments
๐ Why I stopped taking photographs almost altogether
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- "Why I stopped taking photographs almost altogether" | 2023-08-16 | 51 Upvotes 62 Comments
๐ Business Plot
The Business Plot was a political conspiracy in 1933 in the United States. Retired Marine Corps Major General Smedley Butler revealed that wealthy businessmen were plotting to create a fascist veterans' organization with Butler as its leader and use it in a coup d'รฉtat to overthrow President Franklin D. Roosevelt. In 1934, Butler testified before the United States House of Representatives Special Committee on Un-American Activities (the "McCormackโDickstein Committee") on these revelations. No one was prosecuted.
At the time of the incidents, news media dismissed the plot, with a New York Times editorial characterizing it as a "gigantic hoax". While historians have not accepted the notion of a plot, they agree that Butler described one.
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- "Business Plot" | 2020-01-10 | 24 Upvotes 2 Comments
๐ Ilya Zhitomirskiy
Ilya Zhitomirskiy (12 October 1989 โ 12 November 2011) was a Russian-American software developer and entrepreneur. Zhitomirskiy was a co-founder and developer of the Diaspora social network and the Diaspora free software that powers it.
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- "Ilya Zhitomirskiy" | 2013-01-13 | 86 Upvotes 7 Comments
๐ Everything Is a File
"Everything is a file" is an idea that Unix, and its derivatives, handle input/output to and from resources such as documents, hard-drives, modems, keyboards, printers and even some inter-process and network communications as simple streams of bytes exposed through the filesystem name space. Exceptions include semaphores, processes and threads.
The advantage of this approach is that the same set of tools, utilities and APIs can be used on a wide range of resources and a number of file types. When a file is opened, a file descriptor is created, using the file path as an addressing system. The file descriptor is then a byte stream I/O interface on which file operations are performed. File descriptors are also created for objects such as anonymous pipes and network sockets - and therefore a more accurate description of this feature is Everything is a file descriptor.
Additionally, a range of pseudo and virtual filesystems exists which exposes internal kernel data, such as information about processes, to user space in a hierarchical file-like structure. These are mounted into the single file hierarchy.
An example of this purely virtual filesystem is under /proc that exposes many system properties as files. All of these files, in the broader sense of the word, have standard Unix file attributes such as an owner and access permissions, and can be queried by the same classic Unix tools and filters. However, this is not universally considered a fast or portable approach. Some operating systems do not mount /proc by default due to security or speed concerns, relying on system calls instead. It is, though, used heavily by Linux shell utilities, such as procps ps implementation and the widely installed on embedded systems BusyBox. Android Toolbox program depend on it as well.
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- "Everything Is a File" | 2024-01-24 | 44 Upvotes 23 Comments