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🔗 Europe 🔗 Ethnic groups

The Yenish (German: Jenische; French: Yéniche) are an itinerant group in Western Europe who live mostly in Germany, Austria, Switzerland, Luxembourg, Belgium, and parts of France, roughly centred on the Rhineland. A number of theories for the group's origins have been proposed, including that the Yenish descended from members of the marginalized and vagrant poor classes of society of the early modern period, before emerging as a distinct group by the early 19th century. Most of the Yenish became sedentary in the course of the mid-19th to 20th centuries.

🔗 Time 🔗 Solar System/Mars 🔗 Solar System

Various schemes have been used or proposed for timekeeping on the planet Mars independently of Earth time and calendars.

Mars has an axial tilt and a rotation period similar to those of Earth. Thus, it experiences seasons of spring, summer, autumn and winter much like Earth. Coincidentally, the duration of a Martian day is within a few percent of that of an Earth day, which has led to the use of analogous time units. A Mars year is almost twice as long as Earth's, and its orbital eccentricity is considerably larger, which means that the lengths of various Martian seasons differ considerably, and sundial time can diverge from clock time more than on Earth.

🔗 Lists 🔗 Buddhism 🔗 Project-independent assessment

The Buddhist games list is a list of games that Gautama Buddha is reputed to have said that he would not play and that his disciples should likewise not play, because he believed them to be a 'cause for negligence'. This list dates from the 6th or 5th century BCE and is the earliest known list of games.

There is some debate about the translation of some of the games mentioned, and the list given here is based on the translation by T. W. Rhys Davids of the Brahmajāla Sutta and is in the same order given in the original. The list is duplicated in a number of other early Buddhist texts, including the Vinaya Pitaka.

1. Games on boards with 8 or 10 rows. This is thought to refer to ashtapada and dasapada respectively, but later Sinhala commentaries refer to these boards also being used with games involving dice.
2. The same games played on imaginary boards. Akasam astapadam was an ashtapada variant played with no board, literally "astapadam played in the sky". A correspondent in the American Chess Bulletin identifies this as likely the earliest literary mention of a blindfold chess variant.
3. Games of marking diagrams on the floor such that the player can only walk on certain places. This is described in the Vinaya Pitaka as "having drawn a circle with various lines on the ground, there they play avoiding the line to be avoided". Rhys Davids suggests that it may refer to parihāra-patham, a form of hop-scotch.
4. Games where players either remove pieces from a pile or add pieces to it, with the loser being the one who causes the heap to shake (similar to the modern game pick-up sticks).
5. Games of throwing dice.
6. "Dipping the hand with the fingers stretched out in lac, or red dye, or flour-water, and striking the wet hand on the ground or on a wall, calling out 'What shall it be?' and showing the form required—elephants, horses, &c."
7. Ball games.
8. Blowing through a pat-kulal, a toy pipe made of leaves.
9. Ploughing with a toy plough.
10. Playing with toy windmills made from palm leaves.
11. Playing with toy measures made from palm leaves.
12. Playing with toy carts.
13. Playing with toy bows.
14. Guessing at letters traced with the finger in the air or on a friend's back.
15. Guessing a friend's thoughts.
16. Imitating deformities.

Although the modern game of chess had not been invented at the time the list was made, earlier chess-like games such as chaturaji may have existed. H.J.R. Murray refers to Rhys Davids' 1899 translation, noting that the 8×8 board game is most likely ashtapada while the 10×10 game is dasapada. He states that both are race games.

Rocky Mountain BASIC (also RMB or RM-BASIC) is a dialect of the BASIC programming language created by Hewlett-Packard. It was especially popular for control of automatic test equipment using GPIB. It has several features which are or were unusual in BASIC dialects, such as event-driven operation, extensive external I/O support, complex number support, and matrix manipulation functions. Today, RMB is mainly used in environments where an investment in RMB software, hardware, or expertise already exists.

🔗 Mathematics 🔗 Statistics

Itô calculus, named after Kiyosi Itô, extends the methods of calculus to stochastic processes such as Brownian motion (see Wiener process). It has important applications in mathematical finance and stochastic differential equations.

The central concept is the Itô stochastic integral, a stochastic generalization of the Riemann–Stieltjes integral in analysis. The integrands and the integrators are now stochastic processes:

${\displaystyle Y_{t}=\int _{0}^{t}H_{s}\,dX_{s},}$

where H is a locally square-integrable process adapted to the filtration generated by X (Revuz & Yor 1999, Chapter IV), which is a Brownian motion or, more generally, a semimartingale. The result of the integration is then another stochastic process. Concretely, the integral from 0 to any particular t is a random variable, defined as a limit of a certain sequence of random variables. The paths of Brownian motion fail to satisfy the requirements to be able to apply the standard techniques of calculus. So with the integrand a stochastic process, the Itô stochastic integral amounts to an integral with respect to a function which is not differentiable at any point and has infinite variation over every time interval. The main insight is that the integral can be defined as long as the integrand H is adapted, which loosely speaking means that its value at time t can only depend on information available up until this time. Roughly speaking, one chooses a sequence of partitions of the interval from 0 to t and constructs Riemann sums. Every time we are computing a Riemann sum, we are using a particular instantiation of the integrator. It is crucial which point in each of the small intervals is used to compute the value of the function. The limit then is taken in probability as the mesh of the partition is going to zero. Numerous technical details have to be taken care of to show that this limit exists and is independent of the particular sequence of partitions. Typically, the left end of the interval is used.

Important results of Itô calculus include the integration by parts formula and Itô's lemma, which is a change of variables formula. These differ from the formulas of standard calculus, due to quadratic variation terms.

In mathematical finance, the described evaluation strategy of the integral is conceptualized as that we are first deciding what to do, then observing the change in the prices. The integrand is how much stock we hold, the integrator represents the movement of the prices, and the integral is how much money we have in total including what our stock is worth, at any given moment. The prices of stocks and other traded financial assets can be modeled by stochastic processes such as Brownian motion or, more often, geometric Brownian motion (see Black–Scholes). Then, the Itô stochastic integral represents the payoff of a continuous-time trading strategy consisting of holding an amount H_t of the stock at time t. In this situation, the condition that H is adapted corresponds to the necessary restriction that the trading strategy can only make use of the available information at any time. This prevents the possibility of unlimited gains through clairvoyance: buying the stock just before each uptick in the market and selling before each downtick. Similarly, the condition that H is adapted implies that the stochastic integral will not diverge when calculated as a limit of Riemann sums (Revuz & Yor 1999, Chapter IV).

🔗 United States 🔗 Germany 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Military history/Intelligence 🔗 United Kingdom 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Military history/European military history 🔗 Military history/British military history

Operation Epsilon was the codename of a program in which Allied forces near the end of World War II detained ten German scientists who were thought to have worked on Nazi Germany's nuclear program. The scientists were captured between May 1 and June 30, 1945, as part of the Allied Alsos Mission, mainly as part of its Operation Big sweep through southwestern Germany.

They were interned at Farm Hall, a bugged house in Godmanchester, near Cambridge, England, from July 3, 1945, to January 3, 1946. The primary goal of the program was to determine how close Nazi Germany had been to constructing an atomic bomb by listening to their conversations.

🔗 Trains 🔗 Trains/UK Railways 🔗 Trains/Locomotives

LNER Peppercorn Class A1 No. 60163 Tornado is a 4-6-2 steam locomotive completed in 2008 to an original design by Arthur Peppercorn. It is the first new build British mainline steam locomotive since 1960, and the only Peppercorn Class A1 in existence after the original batch were scrapped. In 2017, Tornado became the first steam locomotive to officially reach 100 mph (160 km/h) on British tracks in over 50 years.

After the project was founded by the A1 Steam Locomotive Trust in 1990, construction of Tornado began in 1994 and mostly took place at Darlington Works, with other components manufactured elsewhere. The project was financed through fundraising initiatives, public donations, sponsorship deals, and hiring out Tornado itself for special services. The locomotive was granted its mainline certificate in January 2009, having been designed in compliance with modern safety and certification standards. Tornado has worked on heritage and mainline trains across Britain since 2008. In 2022, it was withdrawn for overhaul.

🔗 Computer science

In computer science, the shunting-yard algorithm is a method for parsing mathematical expressions specified in infix notation. It can produce either a postfix notation string, also known as Reverse Polish notation (RPN), or an abstract syntax tree (AST). The algorithm was invented by Edsger Dijkstra and named the "shunting yard" algorithm because its operation resembles that of a railroad shunting yard. Dijkstra first described the Shunting Yard Algorithm in the Mathematisch Centrum report MR 34/61.

Like the evaluation of RPN, the shunting yard algorithm is stack-based. Infix expressions are the form of mathematical notation most people are used to, for instance "3 + 4" or "3 + 4 × (2 − 1)". For the conversion there are two text variables (strings), the input and the output. There is also a stack that holds operators not yet added to the output queue. To convert, the program reads each symbol in order and does something based on that symbol. The result for the above examples would be (in Reverse Polish notation) "3 4 +" and "3 4 2 1 − × +", respectively.

The shunting-yard algorithm was later generalized into operator-precedence parsing.

🔗 Television

TV detector vans are vans, which, according to the BBC, contain equipment that can detect the presence of television sets in use. The vans are operated by contractors working for the BBC, to enforce the television licensing system in the UK, the Channel Islands and on the Isle of Man. The veracity of their operation has been called into question in the media.

🔗 Business 🔗 Urban studies and planning 🔗 Cities

A company town is a place where practically all stores and housing are owned by the one company that is also the main employer. Company towns are often planned with a suite of amenities such as stores, houses of worship, schools, markets and recreation facilities. They are usually bigger than a model village ("model" in the sense of an ideal to be emulated).

Some company towns have had high ideals, but many have been regarded as controlling and/or exploitative. Others developed more or less in unplanned fashion, such as Summit Hill, Pennsylvania, United States, one of the oldest, which began as an LC&N Co. mining camp and mine site nine miles (14.5 km) from the nearest outside road.