Have a deep view into what people are curious about.

🔗 Time

The Doomsday rule is an algorithm of determination of the day of the week for a given date. It provides a perpetual calendar because the Gregorian calendar moves in cycles of 400 years. The algorithm for mental calculation was devised by John Conway in 1973, drawing inspiration from Lewis Carroll's perpetual calendar algorithm. It takes advantage of each year having a certain day of the week, called the doomsday, upon which certain easy-to-remember dates fall; for example, 4/4, 6/6, 8/8, 10/10, 12/12, and the last day of February all occur on the same day of the week in any year. Applying the Doomsday algorithm involves three steps: Determination of the anchor day for the century, calculation of the doomsday for the year from the anchor day, and selection of the closest date out of those that always fall on the doomsday, e.g., 4/4 and 6/6, and count of the number of days (modulo 7) between that date and the date in question to arrive at the day of the week. The technique applies to both the Gregorian calendar and the Julian calendar, although their doomsdays are usually different days of the week.

The algorithm is simple enough that it can be computed mentally. Conway can usually give the correct answer in under two seconds. To improve his speed, he practices his calendrical calculations on his computer, which is programmed to quiz him with random dates every time he logs on.

🔗 Brands 🔗 Time

Atmos is the brand name of a mechanical torsion pendulum clock manufactured by Jaeger-LeCoultre in Switzerland which does not need to be wound manually. It gets the energy it needs to run from temperature and atmospheric pressure changes in the environment, and can run for years without human intervention.

The clock is driven by a mainspring, which is wound by the expansion and contraction of liquid and gaseous ethyl chloride in an internal hermetically sealed bellows. The ethyl chloride vaporises into an expansion chamber as the temperature rises, compressing a spiral spring; with a fall in temperature the gas condenses and the spring slackens. This motion constantly winds the mainspring. A temperature variation of only one degree in the range between 15 °C (59 °F) and 30 °C (86 °F), or a pressure variation of 3 mmHg, is sufficient for two days' operation.

In order to run the clock on this small amount of energy, everything inside the Atmos has to work in as friction-free a manner as possible. For timekeeping it uses a torsion pendulum, which consumes less energy than an ordinary pendulum. The torsion pendulum has a period of precisely one minute; thirty seconds to rotate in one direction and thirty seconds to return to the starting position. This is thirty times slower than the 0.994 m (39.1 in) seconds pendulum typically found in a longcase clock, where each swing (or half-period) takes one second.

🔗 Physiology 🔗 Physiology/neuro

The majority of studies on sleep creativity have shown that sleep can facilitate insightful behavior and flexible reasoning, and there are several hypotheses about the creative function of dreams. On the other hand, a few recent studies have supported a theory of creative insomnia, in which creativity is significantly correlated with sleep disturbance.

🔗 Telecommunications

Through-the-Earth (TTE) signalling is a type of radio signalling used in mines and caves that uses low-frequency waves to penetrate dirt and rock, which are opaque to higher-frequency conventional radio signals.

In mining, these lower-frequency signals can be relayed underground through various antennas, repeater or mesh configurations, but communication is restricted to line of sight to these antenna and repeaters systems.

🔗 Radio 🔗 Psychology 🔗 Women 🔗 Electronics 🔗 Retailing 🔗 Home Living 🔗 Gender Studies 🔗 Feminism

Wife acceptance factor, wife approval factor, or wife appeal factor (WAF) is an assessment of design elements that either increase or diminish the likelihood a wife will approve the purchase of expensive consumer electronics products such as high-fidelity loudspeakers, home theater systems and personal computers. Stylish, compact forms and appealing colors are commonly considered to have a high WAF. The term is a tongue-in-cheek play on electronics jargon such as "form factor" and "power factor" and derives from the idea that men are predisposed to appreciate gadgetry and performance criteria whereas women must be wooed by visual and aesthetic factors.

🔗 Medicine 🔗 Medicine/Neurology

Gourmand syndrome is a very rare and benign eating disorder that usually occurs six to twelve months after an injury to the frontal lobe. Those with the disorder usually have a right hemisphere frontal or temporal brain lesion typically affecting the cortical areas, basal ganglia or limbic structures. These people develop a new, post-injury passion for gourmet food.

There are two main aspects of gourmand syndrome: first, the fine dining habits and changes to taste, and second, an obsessive component which may result in craving and preservation. Gourmand syndrome can be related to, and shares biological features with, addictive and obsessive disorders. The syndrome was first characterized in 1997.

🔗 Computing 🔗 Mathematics

Finger binary is a system for counting and displaying binary numbers on the fingers of one or more hands. It is possible to count from 0 to 31 (2⁵ − 1) using the fingers of a single hand, from 0 through 1023 (2¹⁰ − 1) if both hands are used, or from 0 to 1,048,575 (2²⁰ − 1) if the toes on both feet are used as well.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software

The Oberon System is a modular, single-user, single-process, multitasking operating system written in the programming language of the same name. It was originally developed in the late 1980s at ETH Zürich. The Oberon System has an unconventional visual text user interface instead of a conventional CLI or GUI. This "TUI" was very innovative in its time and influenced the design of the Acme text editor for the Plan 9 from Bell Labs operating system.

The latest version of the Oberon System, Project Oberon 2013, is still maintained by Niklaus Wirth and a number of collaborators but older ETH versions of the Oberon Systems have been orphaned. The Oberon System also evolved into the multi-process, SMP-capable Bluebottle operating system, with a zooming user interface.

🔗 Biography 🔗 Biography/science and academia 🔗 Astronomy 🔗 Middle Ages 🔗 Middle Ages/History

Ala al-Dīn Ali ibn Muhammed (1403 – 16 December 1474), known as Ali Qushji (Ottoman Turkish/Persian language: علی قوشچی, kuşçu – falconer in Turkish; Latin: Ali Kushgii) was an astronomer, mathematician and physicist originally from Samarkand, who settled in the Ottoman Empire some time before 1472. As a disciple of Ulugh Beg, he is best known for the development of astronomical physics independent from natural philosophy, and for providing empirical evidence for the Earth's rotation in his treatise, Concerning the Supposed Dependence of Astronomy upon Philosophy. In addition to his contributions to Ulugh Beg's famous work Zij-i-Sultani and to the founding of Sahn-ı Seman Medrese, one of the first centers for the study of various traditional Islamic sciences in the Ottoman caliphate, Ali Kuşçu was also the author of several scientific works and textbooks on astronomy.

🔗 Computing

Simula is the name of two simulation programming languages, Simula I and Simula 67, developed in the 1960s at the Norwegian Computing Center in Oslo, by Ole-Johan Dahl and Kristen Nygaard. Syntactically, it is a fairly faithful superset of ALGOL 60, also influenced by the design of Simscript.

Simula 67 introduced objects, classes, inheritance and subclasses, virtual procedures, coroutines, and discrete event simulation, and features garbage collection. Also other forms of subtyping (besides inheriting subclasses) were introduced in Simula derivatives.

Simula is considered the first object-oriented programming language. As its name suggests, the first Simula version by 1962 was designed for doing simulations; Simula 67 though was designed to be a general-purpose programming language and provided the framework for many of the features of object-oriented languages today.

Simula has been used in a wide range of applications such as simulating very-large-scale integration (VLSI) designs, process modeling, communication protocols, algorithms, and other applications such as typesetting, computer graphics, and education. The influence of Simula is often understated, and Simula-type objects are reimplemented in C++, Object Pascal, Java, C#, and many other languages. Computer scientists such as Bjarne Stroustrup, creator of C++, and James Gosling, creator of Java, have acknowledged Simula as a major influence.