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🔗 Computing 🔗 Computer science

In computer science, program synthesis is the task to construct a program that provably satisfies a given high-level formal specification. In contrast to program verification, the program is to be constructed rather than given; however, both fields make use of formal proof techniques, and both comprise approaches of different degrees of automation. In contrast to automatic programming techniques, specifications in program synthesis are usually non-algorithmic statements in an appropriate logical calculus.

The primary application of program synthesis is to relieve the programmer of the burden of writing correct, efficient code that satisfies a specification. However, program synthesis also has applications to superoptimization and inference of loop invariants.

🔗 Computing 🔗 Computing/Computer hardware

The iAPX 432 (Intel Advanced Performance Architecture) is a discontinued computer architecture introduced in 1981. It was Intel's first 32-bit processor design. The main processor of the architecture, the general data processor, is implemented as a set of two separate integrated circuits, due to technical limitations at the time. Although some early 8086, 80186 and 80286-based systems and manuals also used the iAPX prefix for marketing reasons, the iAPX 432 and the 8086 processor lines are completely separate designs with completely different instruction sets.

The project started in 1975 as the 8800 (after the 8008 and the 8080) and was intended to be Intel's major design for the 1980s. Unlike the 8086, which was designed the following year as a successor to the 8080, the iAPX 432 was a radical departure from Intel's previous designs meant for a different market niche, and completely unrelated to the 8080 or x86 product lines.

The iAPX 432 project is considered a commercial failure for Intel, and was discontinued in 1986.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software 🔗 Linux

The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems.

X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting with a mouse and keyboard. X does not mandate the user interface – this is handled by individual programs. As such, the visual styling of X-based environments varies greatly; different programs may present radically different interfaces.

X originated at the Project Athena at Massachusetts Institute of Technology (MIT) in 1984. The X protocol has been at version 11 (hence "X11") since September 1987. The X.Org Foundation leads the X project, with the current reference implementation, X.Org Server, available as free and open source software under the MIT License and similar permissive licenses.

🔗 Mathematics

In mathematics, in the area of harmonic analysis, the fractional Fourier transform (FRFT) is a family of linear transformations generalizing the Fourier transform. It can be thought of as the Fourier transform to the n-th power, where n need not be an integer — thus, it can transform a function to any intermediate domain between time and frequency. Its applications range from filter design and signal analysis to phase retrieval and pattern recognition.

The FRFT can be used to define fractional convolution, correlation, and other operations, and can also be further generalized into the linear canonical transformation (LCT). An early definition of the FRFT was introduced by Condon, by solving for the Green's function for phase-space rotations, and also by Namias, generalizing work of Wiener on Hermite polynomials.

However, it was not widely recognized in signal processing until it was independently reintroduced around 1993 by several groups. Since then, there has been a surge of interest in extending Shannon's sampling theorem for signals which are band-limited in the Fractional Fourier domain.

A completely different meaning for "fractional Fourier transform" was introduced by Bailey and Swartztrauber as essentially another name for a z-transform, and in particular for the case that corresponds to a discrete Fourier transform shifted by a fractional amount in frequency space (multiplying the input by a linear chirp) and evaluating at a fractional set of frequency points (e.g. considering only a small portion of the spectrum). (Such transforms can be evaluated efficiently by Bluestein's FFT algorithm.) This terminology has fallen out of use in most of the technical literature, however, in preference to the FRFT. The remainder of this article describes the FRFT.

🔗 Books 🔗 Sociology

The Power Elite is a 1956 book by sociologist C. Wright Mills, in which Mills calls attention to the interwoven interests of the leaders of the military, corporate, and political elements of society and suggests that the ordinary citizen in modern times is a relatively powerless subject of manipulation by those three entities.

🔗 Military history 🔗 Disaster management 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Lists

A nuclear close call is an incident that could lead to, or could have led to at least one unintended nuclear detonation/explosion. These incidents typically involve a perceived imminent threat to a nuclear-armed country which could lead to retaliatory strikes against the perceived aggressor. The damage caused by international nuclear exchange is not necessarily limited to the participating countries, as the hypothesized rapid climate change associated with even small-scale regional nuclear war could threaten food production worldwide—a scenario known as nuclear famine.

Despite a reduction in global nuclear tensions and major nuclear arms reductions after the end of the Cold War (in 1989), estimated nuclear warhead stockpiles total roughly 15,000 worldwide, with the United States and Russia holding 90% of the total.

Though exact details on many nuclear close calls are hard to come by, the analysis of particular cases has highlighted the importance of a variety of factors in preventing accidents. At an international level, this includes the importance of context and outside mediation; at the national level, effectiveness in government communications, and involvement of key decision-makers; and, at the individual level, the decisive role of individuals in following intuition and prudent decision-making, often in violation of protocol.

🔗 Biography

Jonathan Gillette, known by the pseudonym why the lucky stiff (often abbreviated as _why), is a writer, cartoonist, artist, and programmer notable for his work with the Ruby programming language. Annie Lowrey described him as "one of the most unusual, and beloved, computer programmers" in the world. Along with Yukihiro Matsumoto and David Heinemeier Hansson, he was seen as one of the key figures in the Ruby community.

_why made a presentation enigmatically titled "A Starry Afternoon, a Sinking Symphony, and the Polo Champ Who Gave It All Up for No Reason Whatsoever" at the 2005 O'Reilly Open Source Convention. It explored how to teach programming and make the subject more appealing to adolescents. _why gave a presentation and performed with his band, the Thirsty Cups, at RailsConf in 2006.

On 19 August 2009, _why's accounts on Twitter and GitHub and his personally maintained websites went offline. Shortly before he disappeared, why the lucky stiff tweeted, "programming is rather thankless. u see your works become replaced by superior ones in a year. unable to run at all in a few more."

_why's colleagues have assembled collections of his writings and projects.

Later his website briefly went back online with a detailed explanation of his plans for the future.

🔗 Novels 🔗 Books 🔗 Novels/Short story 🔗 Horror

The King in Yellow is a book of short stories by American writer Robert W. Chambers, first published by F. Tennyson Neely in 1895. The British first edition was published by Chatto & Windus in 1895 (316 pages).

The book contains nine short stories and a sequence of poems; while the first stories belong to the genres of supernatural horror and weird fiction, The King in Yellow progressively transitions towards a more light-hearted tone, ending with romantic stories devoid of horror or supernatural elements. The horror stories are highly esteemed, and it has been described by critics such as E. F. Bleiler, S. T. Joshi, and T. E. D. Klein as a classic in the field of the supernatural. Lin Carter called it "an absolute masterpiece, probably the single greatest book of weird fantasy written in this country between the death of Poe and the rise of Lovecraft", and it was an influence on Lovecraft himself.

The book is named for the eponymous play within the stories which recurs as a motif through the first four stories, a forbidden play which induces madness in those who read it.

🔗 Internet 🔗 Internet culture 🔗 Linguistics 🔗 Linguistics/Applied Linguistics

Usenet () is a worldwide distributed discussion system available on computers. It was developed from the general-purpose Unix-to-Unix Copy (UUCP) dial-up network architecture. Tom Truscott and Jim Ellis conceived the idea in 1979, and it was established in 1980. Users read and post messages (called articles or posts, and collectively termed news) to one or more categories, known as newsgroups. Usenet resembles a bulletin board system (BBS) in many respects and is the precursor to Internet forums that are widely used today. Discussions are threaded, as with web forums and BBSs, though posts are stored on the server sequentially. The name comes from the term "users network".

A major difference between a BBS or web forum and Usenet is the absence of a central server and dedicated administrator. Usenet is distributed among a large, constantly changing conglomeration of servers that store and forward messages to one another via "news feeds". Individual users may read messages from and post messages to a local server, which may be operated by anyone.

Usenet is culturally and historically significant in the networked world, having given rise to, or popularized, many widely recognized concepts and terms such as "FAQ", "flame", sockpuppet, and "spam". In the 1990s, before access to the Internet became commonly affordable, Usenet connections via Fidonet's dial-up BBS networks made long-distance or worldwide discussions and other communication widespread, not needing a server, just (local) telephone service.

🔗 Mass surveillance 🔗 Espionage 🔗 Politics of the United Kingdom

Optic Nerve is a mass surveillance programme run by the British signals intelligence agency Government Communications Headquarters (GCHQ), with help from the US National Security Agency, that surreptitiously collects private webcam still images from users while they are using a Yahoo! webcam application. As an example of the scale, in one 6-month period, the programme is reported to have collected images from 1.8 million Yahoo! user accounts globally. The programme was first reported on in the media in February 2014, from documents leaked by the former National Security Agency contractor Edward Snowden, but dates back to a prototype started in 2008, and was still active in at least 2012.

The leaked documents describe the users under surveillance as "unselected", meaning that data was collected indiscriminately in bulk from users regardless of whether they were an intelligence target or not. The vast majority of affected users would have been completely innocent of any crime or suspicion of a crime. Optic Nerve as described in the documents collected one still image every 5 minutes per user, attempting to comply with human rights legislation. The images were collected in a searchable database, and used for experiments in facial recognition, to monitor known targets, and to discover new targets. The choice of Yahoo! for surveillance was taken because "Yahoo webcam is known to be used by GCHQ targets". Unlike the US NSA, the UK GCHQ is not required by law to minimise the collection from domestic citizens, so UK citizens could have been targeted on the same level as non-UK citizens.

The story was broken by The Guardian in February 2014, and is based on leaked documents dating to between 2008 and 2012. Yahoo! expressed outrage at the programme, when approached by The Guardian, and subsequently called it "a whole new level of violation of our users' privacy." A GCHQ spokesperson stated "It is a long-standing policy that we do not comment on intelligence matters".

Though there were some limits to which photos security analysts were allowed to see, with bulk searches limited to metadata, security analysts were allowed to see "webcam images associated with similar Yahoo identifiers to your known target".