The Publius Enigma is an Internet phenomenon and an unsolved problem that began with cryptic messages posted by a user identifying only as "Publius" to the unmoderated Usenet newsgroup alt.music.pink-floyd through the Penet remailer, a now defunct anonymous information exchange service. The messenger proposed a riddle in connection with the 1994 Pink Floyd album The Division Bell, promising that the answer would lead to a reward.
Guitarist David Gilmour denied any involvement, while album artist Storm Thorgerson was bemused. According to drummer Nick Mason, EMI Records were responsible. It remains unclear if the enigma involves a genuinely solvable puzzle as part of an early Internet-based contest or was a convoluted hoax.
- "Publius Enigma" | 2023-09-22 | 44 Upvotes 16 Comments
Unums (universal numbers) are a family of number formats and arithmetic for implementing real numbers on a computer, proposed by John L. Gustafson in 2015. They are designed as an alternative to the ubiquitous IEEE 754 floating-point standard. The latest version is known as posits.
- "Unum, a Better Number Format" | 2023-09-21 | 11 Upvotes 3 Comments
The High Cost of Free Parking is an urban planning book by UCLA professor Donald Shoup dealing with the costs of free parking on society. It is structured as a criticism of the planning and regulation of parking and recommends that parking be built and allocated according to its fair market value. It incorporates elements of Shoup's Georgist philosophy.
The book was originally published in 2005 by the American Planning Association and the Planners Press. A revised edition was released in 2011 by Routledge.
- "The High Cost of Free Parking" | 2023-09-19 | 68 Upvotes 96 Comments
The escort carrier or escort aircraft carrier (U.S. hull classification symbol CVE), also called a "jeep carrier" or "baby flattop" in the United States Navy (USN) or "Woolworth Carrier" by the Royal Navy, was a small and slow type of aircraft carrier used by the Royal Navy, the Royal Canadian Navy, the United States Navy, the Imperial Japanese Navy and Imperial Japanese Army Air Force in World War II. They were typically half the length and a third the displacement of larger fleet carriers, slower, more-lightly armed and armored, and carried fewer planes. Escort carriers were most often built upon a commercial ship hull, so they were cheaper and could be built quickly. This was their principal advantage as they could be completed in greater numbers as a stop-gap when fleet carriers were scarce. However, the lack of protection made escort carriers particularly vulnerable, and several were sunk with great loss of life. The light carrier (U.S. hull classification symbol CVL) was a similar concept to the escort carrier in most respects, but was fast enough to operate alongside fleet carriers.
Escort carriers were too slow to keep up with the main forces consisting of fleet carriers, battleships, and cruisers. Instead, they were used to escort merchant ship convoys, defending them from enemy threats such as submarines and planes. In the invasions of mainland Europe and Pacific islands, escort carriers provided air support to ground forces during amphibious operations. Escort carriers also served as backup aircraft transports for fleet carriers, and ferried aircraft of all military services to points of delivery.
In the Battle of the Atlantic, escort carriers were used to protect convoys against U-boats. Initially escort carriers accompanied the merchant ships and helped to fend off attacks from aircraft and submarines. As numbers increased later in the war, escort carriers also formed part of hunter-killer groups that sought out submarines instead of being attached to a particular convoy.
In the Pacific theater, CVEs provided air support of ground troops in the Battle of Leyte Gulf. They lacked the speed and weapons to counter enemy fleets, relying on the protection of a Fast Carrier Task Force. However, at the Battle off Samar, one U.S. task force of escort carriers and destroyers managed to successfully defend itself against a much larger Japanese force of battleships and cruisers. The Japanese met a furious defense of carrier aircraft, screening destroyers, and destroyer escorts.
Of the 151 aircraft carriers built in the U.S. during World War II, 122 were escort carriers, though no examples survive. The Casablanca class was the most numerous class of aircraft carrier, with 50 launched. Second was the Bogue class, with 45 launched.
- "USA built 151 Aircraft carriers in WWII" | 2023-09-17 | 43 Upvotes 69 Comments
"The Gods of the Copybook Headings" is a poem by Rudyard Kipling, characterized by biographer Sir David Gilmour as one of several "ferocious post-war eruptions" of Kipling's souring sentiment concerning the state of Anglo-European society. It was first published in the Sunday Pictorial of London on 26 October 1919; in America, it was published as "The Gods of the Copybook Maxims" in Harper's Magazine in January 1920.
In the poem, Kipling's narrator counterposes the "Gods" of the title, who embody eternal truths, against "the Gods of the Market-Place", who represent an optimistic self-deception into which it supposes society has fallen in the early 20th century.
The "copybook headings" to which the title refers were proverbs or maxims, often drawn from sermons and scripture extolling virtue and wisdom, that were printed at the top of the pages of copybooks, special notebooks used by 19th-century British schoolchildren. The students had to copy the maxims repeatedly, by hand, down the page. The exercise was thought to serve simultaneously as a form of moral education and penmanship practice.
- "The Gods of the Copybook Headings" | 2023-09-14 | 56 Upvotes 8 Comments
Percy Edwin Ludgate (2 August 1883 – 16 October 1922) was an Irish amateur scientist who designed the second analytical engine (general-purpose Turing-complete computer) in history.
- "Percy Ludgate" | 2023-09-16 | 140 Upvotes 17 Comments
A rotary woofer is a subwoofer-style loudspeaker which reproduces very low frequency content by using a conventional speaker voice coil's motion to change the pitch (angle) of the blades of an impeller rotating at a constant speed. The pitch of the fan blades is controlled by the audio signal presented to the voice coil, and is able to swing both positive and negative, with respect to a zero pitch spinning blade position. Since the audio amplifier only changes the pitch of the blades, it takes much less power, per dB of generated acoustic sound level, to drive a rotary woofer than to power a conventional subwoofer, which uses a moving electromagnet (voice coil) placed within the field of a stationary permanent magnet to drive a cone which then displaces air. Rotary woofers excel at producing sounds below 20 Hz, below the normal hearing range; when installed in the wall of a sealed room, they can produce audio frequencies down to 0 Hz, a static pressure differential, by simply compressing the air in the sealed room.
- "Rotary Woofer" | 2023-09-15 | 24 Upvotes 2 Comments
Speed tape is an aluminium pressure-sensitive tape used to perform minor repairs on aircraft and racing cars. It is used as a temporary repair material until a more permanent repair can be carried out. It has an appearance similar to duct tape, for which it is sometimes mistaken, but its adhesive is capable of sticking on an airplane fuselage or wing at high speeds, hence the name.
Rubber hose animation was the first animation style that became standardized in the American animation field. The defining feature is the curving motion most things possess, resembling that of a rubber hose. While the style fell out of fashion during the 1930s, there has been a minor revitalization of it in recent years with works such as the video games Cuphead and Bendy and the Ink Machine, and the film Steven Universe: The Movie.
- "Rubber hose animation" | 2023-09-11 | 71 Upvotes 18 Comments
Storm Daniel, also known as Cyclone Daniel, was the deadliest Mediterranean tropical-like cyclone ever recorded as well as the deadliest weather event during 2023. It caused catastrophic damage in Libya and also affected parts of southeastern Europe. Forming as a low-pressure system around 4 September 2023, the storm affected Greece, Bulgaria and also Turkey with extensive flooding. The storm then organized as a Mediterranean Low and was designated as Storm Daniel, in which it soon acquired quasi-tropical characteristics (TLC) and moved toward the coast of Libya, where it caused catastrophic flooding before degenerating into a remnant low. The storm was the result of an Omega block, as a high-pressure zone became sandwiched between two zones of low pressure, the isobars shaping a Greek letter Ω.
- "Mediterranean tropical like Storm Daniel" | 2023-09-12 | 11 Upvotes 3 Comments