Have a deep view into what people are curious about.

🔗 Geography 🔗 Romania 🔗 Ecology 🔗 Caves

Movile Cave (Romanian: Peștera Movile) is a cave near Mangalia, Constanța County, Romania discovered in 1986 by Cristian Lascu a few kilometers from the Black Sea coast. It is notable for its unique groundwater ecosystem abundant in hydrogen sulfide and carbon dioxide, but low in oxygen. Life in the cave has been separated from the outside for the past 5.5 million years and it is based completely on chemosynthesis rather than photosynthesis.

🔗 Websites 🔗 Websites/Computing

Hacker News is a social news website focusing on computer science and entrepreneurship. It is run by Paul Graham's investment fund and startup incubator, Y Combinator. In general, content that can be submitted is defined as "anything that gratifies one's intellectual curiosity".

🔗 Computing 🔗 Computer science

In functional programming, continuation-passing style (CPS) is a style of programming in which control is passed explicitly in the form of a continuation. This is contrasted with direct style, which is the usual style of programming. Gerald Jay Sussman and Guy L. Steele, Jr. coined the phrase in AI Memo 349 (1975), which sets out the first version of the Scheme programming language.John C. Reynolds gives a detailed account of the numerous discoveries of continuations.

A function written in continuation-passing style takes an extra argument: an explicit "continuation"; i.e., a function of one argument. When the CPS function has computed its result value, it "returns" it by calling the continuation function with this value as the argument. That means that when invoking a CPS function, the calling function is required to supply a procedure to be invoked with the subroutine's "return" value. Expressing code in this form makes a number of things explicit which are implicit in direct style. These include: procedure returns, which become apparent as calls to a continuation; intermediate values, which are all given names; order of argument evaluation, which is made explicit; and tail calls, which simply call a procedure with the same continuation, unmodified, that was passed to the caller.

Programs can be automatically transformed from direct style to CPS. Functional and logic compilers often use CPS as an intermediate representation where a compiler for an imperative or procedural programming language would use static single assignment form (SSA). SSA is formally equivalent to a subset of CPS (excluding non-local control flow, which does not occur when CPS is used as intermediate representation). Functional compilers can also use A-normal form (ANF) (but only for languages requiring eager evaluation), rather than with 'thunks' (described in the examples below) in CPS. CPS is used more frequently by compilers than by programmers as a local or global style.

🔗 Computing 🔗 Computing/Computer hardware

The Cyrix 6x86 is a line of sixth-generation, 32-bit x86 microprocessors designed and released by Cyrix in 1995. Cyrix, being a fabless company, had the chips manufactured by IBM and SGS-Thomson. The 6x86 was made as a direct competitor to Intel's Pentium microprocessor line, and was pin compatible. During the 6x86's development, the majority of applications (office software as well as games) performed almost entirely integer operations. The designers foresaw that future applications would most likely maintain this instruction focus. So, to optimize the chip's performance for what they believed to be the most likely application of the CPU, the integer execution resources received most of the transistor budget. This would later prove to be a strategic mistake, as the popularity of the P5 Pentium caused many software developers to hand-optimize code in assembly language, to take advantage of the P5 Pentium's tightly pipelined and lower latency FPU. For example, the highly anticipated first-person shooter Quake used highly optimized assembly code designed almost entirely around the P5 Pentium's FPU. As a result, the P5 Pentium significantly outperformed other CPUs in the game.

🔗 Computing 🔗 Economics 🔗 Systems 🔗 Systems/Cybernetics 🔗 Chile

Project Cybersyn was a Chilean project from 1971–1973 during the presidency of Salvador Allende aimed at constructing a distributed decision support system to aid in the management of the national economy. The project consisted of four modules: an economic simulator, custom software to check factory performance, an operations room, and a national network of telex machines that were linked to one mainframe computer.

Project Cybersyn was based on viable system model theory approach to organizational design, and featured innovative technology for its time: it included a network of telex machines (Cybernet) in state-run enterprises that would transmit and receive information with the government in Santiago. Information from the field would be fed into statistical modeling software (Cyberstride) that would monitor production indicators, such as raw material supplies or high rates of worker absenteeism, in "almost" real time, alerting the workers in the first case and, in abnormal situations, if those parameters fell outside acceptable ranges by a very large degree, also the central government. The information would also be input into economic simulation software (CHECO, for CHilean ECOnomic simulator) that the government could use to forecast the possible outcome of economic decisions. Finally, a sophisticated operations room (Opsroom) would provide a space where managers could see relevant economic data, formulate feasible responses to emergencies, and transmit advice and directives to enterprises and factories in alarm situations by using the telex network.

The principal architect of the system was British operations research scientist Stafford Beer, and the system embodied his notions of organisational cybernetics in industrial management. One of its main objectives was to devolve decision-making power within industrial enterprises to their workforce in order to develop self-regulation of factories.

🔗 United States 🔗 Finance & Investment

The term 3-6-3 Rule describes how the United States retail banking industry operated from the 1950s to the 1980s. The name 3-6-3 refers to the impression that bankers had a stable, comfortable existence by paying 3 percent interest on deposits, lending money out at 6 percent, and being able to "tee off at the golf course by 3 p.m."

The implication was that the banks were less competitive during that period than in subsequent years due to tight regulations that limited the formation and location of banks as well as restrictions on interest rates that could be charged or paid. As a result, bankers had "power and prestige ... while profits were steady and certain". These regulations were loosened in the 1980s.

Richmond Federal Reserve senior economist John R. Walter argues that, although there is evidence that restrictions on banks before the 1980s did limit the competitiveness of banking markets and thereby granted some banks monopoly power, "the regulatory restrictions probably had a limited effect on competition" during the time in question. Chicago Federal Reserve researchers Robert DeYoung and Tara Rice argue that, "Like most good jokes, the 3-6-3 rule mixes a grain of truth with a highly simplified view of reality."

The rule has been noted positively following the late-2000s financial crisis as a preferable way for banks to operate following the bailout of major banks.

Australia's banking system, which was deregulated in the 1990s in a manner similar to that in the U.S., also came to be characterized in the same way as did the United Kingdom's.

🔗 Literature 🔗 Poetry 🔗 Judaism 🔗 Christianity 🔗 Latter Day Saint movement 🔗 Christianity/Bible

Chiastic structure, or chiastic pattern, is a literary technique in narrative motifs and other textual passages. An example of chiastic structure would be two ideas, A and B, together with variants A' and B', being presented as A,B,B',A'. Chiastic structures that involve more components are sometimes called "ring structures", "ring compositions", or, in cases of very ambitious chiasmus, "onion-ring compositions". These may be regarded as chiasmus scaled up from words and clauses to larger segments of text.

These often symmetrical patterns are commonly found in ancient literature such as the epic poetry of the Iliad and the Odyssey. Classicist Bruno Gentili describes this technique as "the cyclical, circular, or 'ring' pattern (ring composition). Here the idea that introduced a compositional section is repeated at its conclusion, so that the whole passage is framed by material of identical content". Meanwhile, in classical prose, scholars often find chiastic narrative techniques in the Histories of Herodotus:

"Herodotus frequently uses ring composition or 'epic regression' as a way of supplying background information for something discussed in the narrative. First an event is mentioned briefly, then its precedents are reviewed in reverse chronological order as far back as necessary; at that point the narrative reverses itself and moves forward in chronological order until the event in the main narrative line is reached again."

Various chiastic structures are also seen in the Hebrew Bible, the New Testament, the Book of Mormon, and the Quran.

🔗 Mathematics

Curry's paradox is a paradox in which an arbitrary claim F is proved from the mere existence of a sentence C that says of itself "If C, then F", requiring only a few apparently innocuous logical deduction rules. Since F is arbitrary, any logic having these rules proves everything. The paradox may be expressed in natural language and in various logics, including certain forms of set theory, lambda calculus, and combinatory logic.

The paradox is named after the logician Haskell Curry. It has also been called Löb's paradox after Martin Hugo Löb, due to its relationship to Löb's theorem.

🔗 Architecture

A saw-tooth roof is a roof comprising a series of ridges with dual pitches either side. The steeper surfaces are glazed to admit daylight and face away from the equator to shield workers and machinery from direct sunlight. This kind of roof admits natural light into a deep plan building or factory. It was therefore most commonly built during the Machine Age from the mid-nineteenth century to the mid-twentieth, when electrification of factories was not yet common.

Many factories of the era had little or no electrical wiring; their main power sources for the machinery were often steam engines driving line shafting, and the lighting was chiefly via daylighting through the windows. Work done at night, when necessary, was typically lit by oil lamps and candles, but many factories closed for the night. Their norm of an early working day (for example, 6 a.m. to 4 p.m.) was not merely a tradition but a functional decision based on this reliance on daylighting. The same was true of the farmer's workday, for the same reason.