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๐ Grue and Bleen: New riddle of induction
Grue and bleen are examples of logical predicates coined by Nelson Goodman in Fact, Fiction, and Forecast to illustrate the "new riddle of induction" โ a successor to Hume's original problem. These predicates are unusual because their application is time-dependent; many have tried to solve the new riddle on those terms, but Hilary Putnam and others have argued such time-dependency depends on the language adopted, and in some languages it is equally true for natural-sounding predicates such as "green." For Goodman they illustrate the problem of projectible predicates and ultimately, which empirical generalizations are law-like and which are not. Goodman's construction and use of grue and bleen illustrates how philosophers use simple examples in conceptual analysis.
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- "Grue and Bleen: New riddle of induction" | 2018-08-12 | 49 Upvotes 52 Comments
๐ Strategic Computing Initiative
The United States government's Strategic Computing Initiative funded research into advanced computer hardware and artificial intelligence from 1983 to 1993. The initiative was designed to support various projects that were required to develop machine intelligence in a prescribed ten-year time frame, from chip design and manufacture, computer architecture to artificial intelligence software. The Department of Defense spent a total of $1 billion on the project.
The inspiration for the program was Japan's fifth generation computer project, an enormous initiative that set aside billions for research into computing and artificial intelligence. As with Sputnik in 1957, the American government saw the Japanese project as a challenge to its technological dominance. The British government also funded a program of their own around the same time, known as Alvey, and a consortium of U.S. companies funded another similar project, the Microelectronics and Computer Technology Corporation.
The goal of SCI, and other contemporary projects, was nothing less than full machine intelligence. "The machine envisioned by SC", according to Alex Roland and Philip Shiman, "would run ten billion instructions per second to see, hear, speak, and think like a human. The degree of integration required would rival that achieved by the human brain, the most complex instrument known to man."
The initiative was conceived as an integrated program, similar to the Apollo moon program, where different subsystems would be created by various companies and academic projects and eventually brought together into a single integrated system. Roland and Shiman wrote that "While most research programs entail tactics or strategy, SC boasted grand strategy, a master plan for an entire campaign."
The project was funded by the Defense Advanced Research Projects Agency and directed by the Information Processing Technology Office (IPTO). By 1985 it had spent $100 million, and 92 projects were underway at 60 institutions: half in industry, half in universities and government labs. Robert Kahn, who directed IPTO in those years, provided the project with its early leadership and inspiration. Clint Kelly managed the SC Initiative for three years and developed many of the specific application programs for DARPA, such as the Autonomous Land Vehicle.
By the late 1980s, it was clear that the project would fall short of realizing the hoped-for levels of machine intelligence. Program insiders pointed to issues with integration, organization, and communication. When Jack Schwarz ascended to the leadership of IPTO in 1987, he cut funding to artificial intelligence research (the software component) "deeply and brutally", "eviscerating" the program (wrote Pamela McCorduck). Schwarz felt that DARPA should focus its funding only on those technologies which showed the most promise. In his words, DARPA should "surf", rather than "dog paddle", and he felt strongly AI was not "the next wave".
Although the program failed to meet its goal of high-level machine intelligence, it did meet some of its specific technical objectives, for example those of autonomous land navigation. The Autonomous Land Vehicle program and its sister Navlab project at Carnegie Mellon University, in particular, laid the scientific and technical foundation for many of the driverless vehicle programs that came after it, such as the Demo II and III programs (ALV being Demo I), Perceptor, and the DARPA Grand Challenge. The use of video cameras plus laser scanners and inertial navigation units pioneered by the SCI ALV program form the basis of almost all commercial driverless car developments today. It also helped to advance the state of the art of computer hardware to a considerable degree. On the software side, the initiative funded development of the Dynamic Analysis and Replanning Tool, a program that handled logistics using artificial intelligence techniques. This was a huge success, saving the Department of Defense billions during Desert Storm.
The project was superseded in the 1990s by the Accelerated Strategic Computing Initiative and then by the Advanced Simulation and Computing Program. These later programs did not include artificial general intelligence as a goal, but instead focused on supercomputing for large scale simulation, such as atomic bomb simulations. The Strategic Computing Initiative of the 1980s is distinct from the 2015 National Strategic Computing Initiativeโthe two are unrelated.
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- "Strategic Computing Initiative" | 2024-06-09 | 36 Upvotes 9 Comments
๐ Space roar
Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE) is a program which utilizes high-altitude balloon instrument package intended to measure the heating of the universe by the first stars and galaxies after the big bang and search for the signal of relic decay or annihilation. In July 2006 a strong residual radio source was found using the radiometer, approximately six times what is predicted by theory. This phenomenon is known as "space roar" and remains an unsolved problem in astrophysics.
ARCADE has been funded by the NASA's Science Mission Directorate under the Astronomy and Physics Research and Analysis Suborbital Investigation program. The program is composed of a team led by Alan Kogut of NASA's Goddard Space Flight Center. ARCADE was launched from NASA's Columbia Scientific Balloon Facility in Palestine, Texas, conducted under the auspices of the Balloon Program Office at Wallops Flight Facility. The balloon flew to an altitude of 120,000 feet (37ย km), viewing about 7% of the sky during its observations.
The instrument is designed to detect radiation at centimeter wavelengths. The craft contained seven radiometers which were cooled to 2.7ย K (โ270.45ย ยฐC; โ454.81ย ยฐF) using liquid helium, with the intent to measure temperature differences as small as 1/1000 of a degree against a background which is only 3ย K (โ270.15ย ยฐC; โ454.27ย ยฐF). The optics in the instrument package were placed near the top of the dewar flask which cooled them in order to prevent the instruments from seeing the walls of the container, thereby simplifying the processing of the observational data. This design choice necessitated the use of superfluid pumps in order to drench the radiometers in liquid helium. The design also utilized heaters in order to create a cloud of helium gas, in place of using a (relatively warm) window, which also simplified processing of the observational data.
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- "Space roar" | 2013-10-13 | 113 Upvotes 7 Comments
๐ Zone System
The Zone System is a photographic technique for determining optimal film exposure and development, formulated by Ansel Adams and Fred Archer. Adams described the Zone System as "[...] not an invention of mine; it is a codification of the principles of sensitometry, worked out by Fred Archer and myself at the Art Center School in Los Angeles, around 1939โ40."
The technique is based on the late 19th century sensitometry studies of Hurter and Driffield. The Zone System provides photographers with a systematic method of precisely defining the relationship between the way they visualize the photographic subject and the final results. Although it originated with black-and-white sheet film, the Zone System is also applicable to roll film, both black-and-white and color, negative and reversal, and to digital photography.
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- "Zone System" | 2022-03-18 | 23 Upvotes 12 Comments
๐ The Origin of Consciousness in the Breakdown of the Bicameral Mind
Julian Jaynes (February 27, 1920 โ November 21, 1997) was an American researcher in psychology at Yale and Princeton for nearly 25 years and best known for his 1976 book The Origin of Consciousness in the Breakdown of the Bicameral Mind. His career was dedicated to the problem of consciousness, โโฆthe difference between what others see of us and our sense of our inner selves and the deep feelings that sustain it. โฆ Men have been conscious of the problem of consciousness almost since consciousness began.โ Jaynes's solution touches on many disciplines, including neuroscience, linguistics, psychology, archeology, history, religion and analysis of ancient texts.
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- "The Origin of Consciousness in the Breakdown of the Bicameral Mind" | 2014-05-26 | 52 Upvotes 60 Comments
๐ Toxic squash syndrome
Cucurbitacin is a class of biochemical compounds that some plants โ notably members of the pumpkin and gourd family, Cucurbitaceae โ produce and which function as a defence against herbivores. Cucurbitacins are chemically classified as triterpenes, formally derived from cucurbitane, a triterpene hydrocarbon โ specifically, from the unsaturated variant cucurbit-5-ene, or 19(10โ9ฮฒ)-abeo-10ฮฑ-lanost-5-ene. They often occur as glycosides. They and their derivatives have been found in many plant families (including Brassicaceae, Cucurbitaceae, Scrophulariaceae, Begoniaceae, Elaeocarpaceae, Datiscaceae, Desfontainiaceae, Polemoniaceae, Primulaceae, Rubiaceae, Sterculiaceae, Rosaceae, and Thymelaeaceae), in some mushrooms (including Russula and Hebeloma) and even in some marine mollusks.
Cucurbitacins may be a taste deterrent in plants foraged by some animals and in some edible plants preferred by humans, like cucumbers and zucchinis. In laboratory research, cucurbitacins have cytotoxic properties and are under study for their potential biological activities.
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- "Toxic squash syndrome" | 2022-07-09 | 64 Upvotes 51 Comments
๐ The Article in the Most Languages
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- "The Article in the Most Languages" | 2025-08-09 | 241 Upvotes 77 Comments
๐ Battle of Los Angeles
The Battle of Los Angeles, also known as the Great Los Angeles Air Raid, is the name given by contemporary sources to a rumored attack on the mainland United States by Imperial Japan and the subsequent anti-aircraft artillery barrage which took place from late 24 February to early 25 February 1942, over Los Angeles, California. The incident occurred less than three months after the U.S. entered World War II in response to the Imperial Japanese Navy's surprise attack on Pearl Harbor, and one day after the bombardment of Ellwood near Santa Barbara on 23 February. Initially, the target of the aerial barrage was thought to be an attacking force from Japan, but speaking at a press conference shortly afterward, Secretary of the Navy Frank Knox called the purported attack a "false alarm". Newspapers of the time published a number of reports and speculations of a cover-up.
When documenting the incident in 1949, the United States Coast Artillery Association identified a meteorological balloon sent aloft at 1:00ย am as having "started all the shooting" and concluded that "once the firing started, imagination created all kinds of targets in the sky and everyone joined in". In 1983, the U.S. Office of Air Force History attributed the event to a case of "war nerves" triggered by a lost weather balloon and exacerbated by stray flares and shell bursts from adjoining batteries.
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- "Battle of Los Angeles" | 2021-03-05 | 18 Upvotes 5 Comments
๐ NEEMO
NASA Extreme Environment Mission Operations, or NEEMO, is a NASA analog mission that sends groups of astronauts, engineers and scientists to live in Aquarius underwater laboratory, the world's only undersea research station, for up to three weeks at a time in preparation for future space exploration.
Aquarius is an underwater habitat 3.5 miles (5.6ย km) off Key Largo, Florida, in the Florida Keys National Marine Sanctuary. It is deployed on the ocean floor next to deep coral reefs 62 feet (19ย m) below the surface.
NASA has used it since 2001 for a series of space exploration simulation missions, usually lasting 7 to 14 days, with space research mainly conducted by international astronauts. The mission had cost about 500ย million U.S. dollars. The crew members are called aquanauts (as they live underwater at depth pressure for a period equal to or greater than 24 continuous hours without returning to the surface), and they perform EVAs in the underwater environment. A technique known as saturation diving allows the aquanauts to live and work underwater for days or weeks at a time. After twenty four hours underwater at any depth, the human body becomes saturated with dissolved gas. With saturation diving, divers can accurately predict exactly how much time they need to decompress before returning to the surface. This information limits the risk of decompression sickness. By living in the Aquarius habitat and working at the same depth on the ocean floor, NEEMO crews are able to remain underwater for the duration of their mission.
For NASA, the Aquarius habitat and its surroundings provide a convincing analog for space exploration. Much like space, the undersea world is a hostile, alien place for humans to live. NEEMO crew members experience some of the same challenges there that they would on a distant asteroid, planet (i.e. Mars) or Moon. During NEEMO missions, the aquanauts are able to simulate living on a spacecraft and test spacewalk techniques for future space missions. Working in space and underwater environments requires extensive planning and sophisticated equipment. The underwater condition has the additional benefit of allowing NASA to "weight" the aquanauts to simulate different gravity environments.
Until 2012, Aquarius was owned by the National Oceanic and Atmospheric Administration (NOAA) and operated by the National Undersea Research Center (NURC) at the University of North CarolinaโWilmington as a marine biology study base.
Since 2013, Aquarius is owned by Florida International University (FIU). As part of the FIU Marine Education and Research Initiative, the Medina Aquarius Program is dedicated to the study and preservation of marine ecosystems worldwide and is enhancing the scope and impact of FIU on research, educational outreach, technology development, and professional training. At the heart of the program is the Aquarius Reef Base.
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- "NEEMO" | 2022-12-10 | 74 Upvotes 16 Comments
๐ A True Story
A True Story (Ancient Greek: แผฮปฮทฮธแฟ ฮดฮนฮทฮณฮฎฮผฮฑฯฮฑ, Alฤthฤ diฤgฤmata; Latin: Vera Historia or Latin: Verae Historiae) is a novel written in the second century AD by Lucian of Samosata, a Greek-speaking author of Assyrian descent. The novel is a satire of outlandish tales which had been reported in ancient sources, particularly those which presented fantastic or mythical events as if they were true. It is Lucian's best-known work.
It is the earliest known work of fiction to include travel to outer space, alien lifeforms, and interplanetary warfare. As such, A True Story has been described as "the first known text that could be called science fiction". However the work does not fit into typical literary genres: its multilayered plot and characters have been interpreted as science fiction, fantasy, satire or parody, and have been the subject of much scholarly debate.
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- "A True Story" | 2018-10-15 | 525 Upvotes 72 Comments