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πŸ”— OODA Loop

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Systems πŸ”— Systems/Systems engineering

The OODA loop is the cycle observe–orient–decide–act, developed by military strategist and United States Air Force Colonel John Boyd. Boyd applied the concept to the combat operations process, often at the operational level during military campaigns. It is now also often applied to understand commercial operations and learning processes. The approach explains how agility can overcome raw power in dealing with human opponents. It is especially applicable to cyber security and cyberwarfare.

The OODA loop has become an important concept in litigation, business, law enforcement, management education, and military strategy. According to Boyd, decision-making occurs in a recurring cycle of observe–orient–decide–act. An entity (whether an individual or an organization) that can process this cycle quickly, observing and reacting to unfolding events more rapidly than an opponent, can thereby "get inside" the opponent's decision cycle and gain the advantage.

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πŸ”— Ousterhout's Dichotomy

πŸ”— Computing πŸ”— Computer science

Ousterhout's dichotomy is computer scientist John Ousterhout's categorization that high-level programming languages tend to fall into two groups, each with distinct properties and uses: system programming languages and scripting languages – compare programming in the large and programming in the small. This distinction underlies the design of his language Tcl.

System programming languages (or applications languages) usually have the following properties:

  • They are typed statically
  • They support creating complex data structures
  • Programs in them are compiled into machine code
  • Programs in them are meant to operate largely independently of other programs

System programming languages tend to be used for components and applications with large amounts of internal functionality such as operating systems, database servers, and Web browsers. These applications typically employ complex algorithms and data structures and require high performance. Prototypical examples of system programming languages include C and Modula-2.

By contrast, scripting languages (or glue languages) tend to have the following properties:

  • They are typed dynamically
  • They have little or no provision for complex data structures
  • Programs in them (scripts) are interpreted

Scripting languages tend to be used for applications where most of the functionality comes from other programs (often implemented in system programming languages); the scripts are used to glue together other programs or add additional layers of functionality on top of existing programs. Ousterhout claims that scripts tend to be short and are often written by less sophisticated programmers, so execution efficiency is less important than simplicity and ease of interaction with other programs. Common applications for scripting include Web page generation, report generation, graphical user interfaces, and system administration. Prototypical examples of scripting languages include AppleScript, C shell, DOS batch files, and Tcl.

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πŸ”— Attempto Controlled English

πŸ”— Computer science πŸ”— Linguistics πŸ”— Languages

Attempto Controlled English (ACE) is a controlled natural language, i.e. a subset of standard English with a restricted syntax and restricted semantics described by a small set of construction and interpretation rules. It has been under development at the University of Zurich since 1995. In 2013, ACE version 6.7 was announced.

ACE can serve as knowledge representation, specification, and query language, and is intended for professionals who want to use formal notations and formal methods, but may not be familiar with them. Though ACE appears perfectly natural – it can be read and understood by any speaker of English – it is in fact a formal language.

ACE and its related tools have been used in the fields of software specifications, theorem proving, text summaries, ontologies, rules, querying, medical documentation and planning.

Here are some simple examples:

  1. Every woman is a human.
  2. A woman is a human.
  3. A man tries-on a new tie. If the tie pleases his wife then the man buys it.

ACE construction rules require that each noun be introduced by a determiner (a, every, no, some, at least 5, ...). Regarding the list of examples above, ACE interpretation rules decide that (1) is interpreted as universally quantified, while (2) is interpreted as existentially quantified. Sentences like "Women are human" do not follow ACE syntax and are consequently not valid.

Interpretation rules resolve the anaphoric references in (3): the tie and it of the second sentence refer to a new tie of the first sentence, while his and the man of the second sentence refer to a man of the first sentence. Thus an ACE text is a coherent entity of anaphorically linked sentences.

The Attempto Parsing Engine (APE) translates ACE texts unambiguously into discourse representation structures (DRS) that use a variant of the language of first-order logic. A DRS can be further translated into other formal languages, for instance AceRules with various semantics, OWL, and SWRL. Translating an ACE text into (a fragment of) first-order logic allows users to reason about the text, for instance to verify, to validate, and to query it.

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πŸ”— International Reply Coupon

πŸ”— International relations πŸ”— Philately πŸ”— Amateur radio

An international reply coupon (IRC) is a coupon that can be exchanged for one or more postage stamps representing the minimum postage for an unregistered priority airmail letter of up to twenty grams sent to another Universal Postal Union (UPU) member country. IRCs are accepted by all UPU member countries.

UPU member postal services are obliged to exchange an IRC for postage, but are not obliged to sell them.

The purpose of the IRC is to allow a person to send someone in another country a letter, along with the cost of postage for a reply. If the addressee is within the same country, there is no need for an IRC because a self-addressed stamped envelope (SASE) or return postcard will suffice; but if the addressee is in another country an IRC removes the necessity of acquiring foreign postage or sending appropriate currency.

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πŸ”— Man on the Clapham Omnibus

πŸ”— Law πŸ”— England

The man on the Clapham omnibus is a hypothetical ordinary and reasonable person, used by the courts in English law where it is necessary to decide whether a party has acted as a reasonable person would – for example, in a civil action for negligence. The character is a reasonably educated, intelligent but nondescript person, against whom the defendant's conduct can be measured.

The term was introduced into English law during the Victorian era, and is still an important concept in British law. It is also used in other Commonwealth common law jurisdictions, sometimes with suitable modifications to the phrase as an aid to local comprehension. The route of the original "Clapham omnibus" is unknown but London Buses route 88 was briefly branded as "the Clapham Omnibus" in the 1990s and is sometimes associated with the term.

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πŸ”— The King in Yellow

πŸ”— Novels πŸ”— Books πŸ”— Novels/Short story πŸ”— 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.

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πŸ”— Airbus Beluga

πŸ”— Aviation πŸ”— Aviation/aircraft

The Airbus A300-600ST (Super Transporter), or Beluga, is a version of the standard A300-600 wide-body airliner modified to carry aircraft parts and outsize cargo. It received the official name of Super Transporter early on; however, the name Beluga, a whale it resembles, gained popularity and has since been officially adopted. The Beluga XL, based on the Airbus A330 with similar modifications and dimensions, was developed by Airbus to replace the type in January 2020.

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πŸ”— Peak car

πŸ”— Climate change πŸ”— Environment πŸ”— Transport πŸ”— Urban studies and planning

Peak car (also peak car use or peak travel) is a hypothesis that motor vehicle distance traveled per capita, predominantly by private car, has peaked and will now fall in a sustained manner. The theory was developed as an alternative to the prevailing market saturation model, which suggested that car use would saturate and then remain reasonably constant, or to GDP-based theories which predict that traffic will increase again as the economy improves, linking recent traffic reductions to the Great Recession of 2008.

The theory was proposed following reductions, which have now been observed in Australia, Belgium, France, Germany, Iceland, Japan (early 1990s), New Zealand, Sweden, the United Kingdom (many cities from about 1994) and the United States. A study by Volpe Transportation in 2013 noted that average miles driven by individuals in the United States has been declining from 900 miles (1,400Β km) per month in 2004 to 820 miles (1,320Β km) in July 2012, and that the decline had continued since the recent upturn in the US economy.

A number of academics have written in support of the theory, including Phil Goodwin, formerly Director of the transport research groups at Oxford University and UCL, and David Metz, a former Chief Scientist of the UK Department of Transport. The theory is disputed by the UK Department for Transport, which predicts that road traffic in the United Kingdom will grow by 50% by 2036, and Professor Stephen Glaister, Director of the RAC Foundation, who say traffic will start increasing again as the economy improves. Unlike peak oil, a theory based on a reduction in the ability to extract oil due to resource depletion, peak car is attributed to more complex and less understood causes.

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πŸ”— I Get This Call Every Day

πŸ”— Video games

I Get This Call Every Day is a 2012 point-and-click video game developed and published by Toronto-based developer David S Gallant. It was released for Microsoft Windows and OS X on December 21, 2012. It focuses on a call received by an employee of a customer service call centre; the player must navigate through the call without irritating the caller or breaking confidentiality laws. Gallant was fired from his job at a call centre as a direct result of publishing the game.

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πŸ”— Milankovitch Cycles

πŸ”— Climate change πŸ”— Environment πŸ”— Geology

Milankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years. The term is named for Serbian geophysicist and astronomer Milutin Milanković. In the 1920s, he hypothesized that variations in eccentricity, axial tilt, and precession resulted in cyclical variation in the solar radiation reaching the Earth, and that this orbital forcing strongly influenced climatic patterns on Earth.

Similar astronomical hypotheses had been advanced in the 19th century by Joseph Adhemar, James Croll and others, but verification was difficult because there was no reliably dated evidence, and because it was unclear which periods were important.

Now, materials on Earth that have been unchanged for millennia (obtained via ice, rock, and deep ocean cores) are being studied to indicate the history of Earth's climate. Though they are consistent with the Milankovitch hypothesis, there are still several observations that the hypothesis does not explain.

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