New Articles (Page 329)
To stay up to date you can also follow on Mastodon.
π Minivac 601
Minivac 601 Digital Computer Kit was an electromechanical digital computer system created by information theory pioneer Claude Shannon as an educational toy using digital circuits.
Discussed on
- "Minivac 601" | 2018-08-04 | 55 Upvotes 10 Comments
π Trout Tickling
Trout tickling is the art of rubbing the underbelly of a trout with fingers. If done properly, the trout will go into a trance after a minute or so, and can then easily be thrown onto the nearest bit of dry land.
Discussed on
- "Trout Tickling" | 2018-07-31 | 66 Upvotes 25 Comments
- "Trout tickling" | 2015-11-08 | 38 Upvotes 15 Comments
π Sabre (computer system)
Sabre Global Distribution System, owned by Sabre Corporation, is used by travel agents and companies around the world to search, price, book, and ticket travel services provided by airlines, hotels, car rental companies, rail providers and tour operators. Sabre aggregates airlines, hotels, online and offline travel agents and travel buyers.
Discussed on
- "Sabre (computer system)" | 2018-07-30 | 65 Upvotes 30 Comments
π Turbo Button
On personal computers, the turbo button is a button which provides two run states for the computer: normal speed or an enhanced "turbo" speed. It was relatively common on personal computers using the Intel 80286, Intel 80386 and Intel 80486 processors, from the mid 1980s to mid 1990s.
The name is inspired by turbocharger, a turbine-driven forced induction device that increases an engine's power and efficiency.
Discussed on
- "Turbo Button" | 2018-07-29 | 195 Upvotes 113 Comments
π Vanadium redox battery
The vanadium redox battery (VRB), also known as the vanadium flow battery (VFB) or vanadium redox flow battery (VRFB), is a type of rechargeable flow battery that employs vanadium ions in different oxidation states to store chemical potential energy. The vanadium redox battery exploits the ability of vanadium to exist in solution in four different oxidation states, and uses this property to make a battery that has just one electroactive element instead of two. For several reasons, including their relative bulkiness, most vanadium batteries are currently used for grid energy storage, i.e., attached to power plants or electrical grids.
The possibility of creating a vanadium flow battery was explored by Pissoort in the 1930s, NASA researchers in the 1970s, and Pellegri and Spaziante in the 1970s, but none of them were successful in demonstrating the technology. The first successful demonstration of the all-vanadium redox flow battery which employed vanadium in a solution of sulfuric acid in each half was by Maria Skyllas-Kazacos at the University of New South Wales in the 1980s. Her design used sulfuric acid electrolytes, and was patented by the University of New South Wales in Australia in 1986.
The main advantages of the vanadium redox battery are that it can offer almost unlimited energy capacity simply by using larger electrolyte storage tanks; it can be left completely discharged for long periods with no ill effects; if the electrolytes are accidentally mixed, the battery suffers no permanent damage; a single state of charge between the two electrolytes avoids the capacity degradation due to a single cell in non-flow batteries; the electrolyte is aqueous and inherently safe and non-flammable; and the generation 3 formulation using a mixed acid solution developed by the Pacific Northwest National Laboratory operates over a wider temperature range allowing for passive cooling. VRFBs can be used at depth of discharge (DOD) around 90% and more, i.e. deeper DODs than solid-state batteries (e.g. lithium-based and sodium-based batteries, which are usually specified with DOD=80%). In addition, VRFBs exhibit very long cycle lives: most producers specify cycle durability in excess of 15,000-20,000 charge/discharge cycles. These values are far beyond the cycle lives of solid-state batteries, which is usually in the order of 4,000-5,000 charge/discharge cycles. Consequently, the levelized cost of energy (LCOE, i.e. the system cost divided by the usable energy, the cycle life, and round-trip efficiency) of present VRFB systems is typically in the order of a few tens of $ cents or β¬ cents, namely much lower than the LCOEs of equivalent solid-state batteries and close to the targets of $0.05 and β¬0.05, stated by the US Department of Energy and the European Commission Strategic Energy Technology (SET) Plan, respectively.
The main disadvantages with vanadium redox technology are a relatively poor energy-to-volume ratio in comparison with standard storage batteries, and the relatively poor round trip efficiency. Furthermore, the aqueous electrolyte makes the battery heavy and therefore only useful for stationary applications. Another disadvantage is the relatively high toxicity of oxides of vanadium (see vanadium Β§Β Safety).
Numerous companies and organizations involved in funding and developing vanadium redox batteries include Avalon Battery, Vionx (formerly Premium Power), UniEnergy Technologies and Ashlawn Energy in the United States; Renewable Energy Dynamics Technology in Ireland; Enerox GmbH (formerly Gildemeister energy storage) in Austria; Cellennium in Thailand; Rongke Power in China; Prudent Energy in China; Sumitomo in Japan; H2, Inc. in South Korea; redT in Britain., Australian Vanadium in Australia, and the now defunct Imergy (formerly Deeya). Lately, also several smaller size vanadium redox flow batteries were brought to market (for residential applications) mainly from StorEn Technologies (USA), Schmid Group, VoltStorage and Volterion (all three from Germany), VisBlue (Denmark) or Pinflow energy storage (Czechia).
Discussed on
- "Vanadium redox battery" | 2018-07-28 | 35 Upvotes 31 Comments
π Wikimedia Foundation v. NSA
Wikimedia Foundation, et al. v. National Security Agency, et al. is a lawsuit filed by the American Civil Liberties Union (ACLU) on behalf of the Wikimedia Foundation and several other organizations against the National Security Agency (NSA), the United States Department of Justice (DOJ), and other named individuals, alleging mass surveillance of Wikipedia users carried out by the NSA. The suit claims the surveillance system, which NSA calls "Upstream", breaches the First Amendment to the United States Constitution, which protects freedom of speech, and the Fourth Amendment to the United States Constitution, which prohibits unreasonable searches and seizures.
The suit was filed in the United States District Court for the District of Maryland as the NSA is based in Fort Meade, Maryland. The suit was dismissed in October 2015 by Judge T. S. Ellis III; this decision was appealed four months later to the Fourth Circuit Court of Appeals by the Wikimedia Foundation. The Court of Appeals found that the dismissal was valid for all of the plaintiffs except the Foundation, whose allegations the court found "plausible" enough to have legal standing for the case to be remanded to the lower court.
The original plaintiffs besides the Wikimedia Foundation were the National Association of Criminal Defense Lawyers, Human Rights Watch, Amnesty International USA, the PEN American Center, the Global Fund for Women, The Nation magazine, the Rutherford Institute, and the Washington Office on Latin America.
Discussed on
- "Wikimedia Foundation v. NSA" | 2018-07-27 | 19 Upvotes 3 Comments
π Here is one hand
Here is one hand is an epistemological argument created by George Edward Moore in reaction against philosophical skepticism and in support of common sense.
The argument takes the following form:
- Here is one hand,
- And here is another.
- There are at least two external objects in the world.
- Therefore, an external world exists.
π Launch loop
A launch loop or Lofstrom loop is a proposed system for launching objects into orbit using a moving cable-like system situated inside a sheath attached to the Earth at two ends and suspended above the atmosphere in the middle. The design concept was published by Keith Lofstrom and describes an active structure maglev cable transport system that would be around 2,000Β km (1,240Β mi) long and maintained at an altitude of up to 80Β km (50Β mi). A launch loop would be held up at this altitude by the momentum of a belt that circulates around the structure. This circulation, in effect, transfers the weight of the structure onto a pair of magnetic bearings, one at each end, which support it.
Launch loops are intended to achieve non-rocket spacelaunch of vehicles weighing 5 metric tons by electromagnetically accelerating them so that they are projected into Earth orbit or even beyond. This would be achieved by the flat part of the cable which forms an acceleration track above the atmosphere.
The system is designed to be suitable for launching humans for space tourism, space exploration and space colonization, and provides a relatively low 3g acceleration.
Discussed on
- "Launch loop" | 2018-07-26 | 116 Upvotes 49 Comments
- "The Lofstrom Loop" | 2015-11-30 | 30 Upvotes 19 Comments
π Role-playing game theory
A role-playing game theory is the ludology of role-playing games (RPGs) where they are studied as a social or artistic phenomenon. RPG theories seek to understand what role-playing games are, how they function, and how the process can be refined in order to improve the gaming experience and produce more useful game products.
Discussed on
- "Role-playing game theory" | 2018-07-24 | 97 Upvotes 38 Comments