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🔗 Computer science 🔗 Mathematics

CORDIC (for COordinate Rotation DIgital Computer), also known as Volder's algorithm, or: Digit-by-digit method Circular CORDIC (Jack E. Volder), Linear CORDIC, Hyperbolic CORDIC (John Stephen Walther), and Generalized Hyperbolic CORDIC (GH CORDIC) (Yuanyong Luo et al.), is a simple and efficient algorithm to calculate trigonometric functions, hyperbolic functions, square roots, multiplications, divisions, and exponentials and logarithms with arbitrary base, typically converging with one digit (or bit) per iteration. CORDIC is therefore also an example of digit-by-digit algorithms. CORDIC and closely related methods known as pseudo-multiplication and pseudo-division or factor combining are commonly used when no hardware multiplier is available (e.g. in simple microcontrollers and FPGAs), as the only operations it requires are additions, subtractions, bitshift and lookup tables. As such, they all belong to the class of shift-and-add algorithms. In computer science, CORDIC is often used to implement floating-point arithmetic when the target platform lacks hardware multiply for cost or space reasons.

🔗 Color

RAL is a colour management system used in Europe that is created and administered by the German RAL gGmbH (RAL non-profit LLC), which is a subsidiary of the German RAL Institute. In colloquial speech, RAL refers to the RAL Classic system, mainly used for varnish and powder coating, but now plastics as well. Approved RAL products are provided with a hologram to make unauthorised versions difficult to produce. Imitations may show different hue and colour when observed under various light sources.

🔗 Sweden 🔗 Scouting

The Wallenberg family are a prominent Swedish family, Europe's pre-eminent, most powerful business family and dynasty, renowned as bankers, industrialists, politicians, bureaucrats, and diplomats.

The Wallenberg sphere's holdings employ about 600,000 people and have sales of $154 billion a year.

The Wallenberg empire consists of 16 Wallenberg Foundations, Foundation Asset Management (FAM), Investor AB, Patricia Industries and Wallenberg Investments AB.

The Wallenbergs control and are majority owners of most large Swedish industrial groups, such as world leading telecommunication multinational Ericsson, Scandinavian and Baltic bank giant Skandinaviska Enskilda Banken, one of the world's largest paper and pulp multinationals Stora Enso, Wärtsilä, world's second largest appliance maker Electrolux, one of the world's largest power, automation and robotics multinationals ABB, one of Europe's largest aerospace and arms manufacturers SAAB, SAS Group, world's largest ball-bearing company SKF, Atlas Copco, pharmaceutical multinational Astra Zeneca, Nasdaq, Inc., Husqvarna, the Stockholm football club AIK, investment company Investor AB, the Grand Group hotel, BraunAbility, Epiroc, world's largest powdered metal company Höganäs AB, IPCO, Laborie, EQT Partners, Nefab, Permobil, Piab, Sobi, Sarnova, 3 Scandinavia, Kopparfors Skogar, Hylte Bruk AB and so on.

Former holdings include among others Scania AB and Saab Automobile.

In the 1970s, the Wallenberg family businesses employed 40% of Sweden's industrial workforce and represented 40% of the total worth of the Stockholm stock market.

Wallenbergs, through the Knut and Alice Wallenberg Foundation, allocate annually SEK 2 billion to science and research, which makes the Knut and Alice Wallenberg Foundation one of the largest private research foundations in Europe, and has, until 2020, awarded SEK 31.2 billion in grants.

The most famous of the Wallenbergs, Raoul Wallenberg, a diplomat, worked in Budapest, Hungary, during World War II to rescue Jews from the Holocaust. Between July and December 1944, he issued protective passports and housed Jews, saving tens of thousands of Jewish lives.

🔗 Cryptography 🔗 Cryptography/Computer science

Shamir's Secret Sharing is an algorithm in cryptography created by Adi Shamir. It is a form of secret sharing, where a secret is divided into parts, giving each participant its own unique part.

To reconstruct the original secret, a minimum number of parts is required. In the threshold scheme this number is less than the total number of parts. Otherwise all participants are needed to reconstruct the original secret.

🔗 Numismatics 🔗 Numismatics/Cryptocurrency 🔗 Cryptocurrency

Base58 is a group of binary-to-text encoding schemes used to represent large integers as alphanumeric text, introduced by Satoshi Nakamoto for use with Bitcoin. It has since been applied to other cryptocurrencies and applications. It is similar to Base64 but has been modified to avoid both non-alphanumeric characters and letters which might look ambiguous when printed. It is therefore designed for human users who manually enter the data, copying from some visual source, but also allows easy copy and paste because a double-click will usually select the whole string.

Compared with Base64, the following similar-looking letters are omitted: 0 (zero), O (capital o), I (capital i) and l (lower case L) as well as the non-alphanumeric characters + (plus) and / (slash). In contrast with Base64, the digits of the encoding do not line up well with byte boundaries of the original data. For this reason, the method is well-suited to encode large integers, but not designed to encode longer portions of binary data. The actual order of letters in the alphabet depends on the application, which is the reason why the term “Base58” alone is not enough to fully describe the format. A variant, Base56, excludes 1 (one) and o (lowercase o) compared with Base 58.

Base58Check is a Base58 encoding format that unambiguously encodes the type of data in the first few characters and includes an error detection code in the last few characters.

🔗 Video games 🔗 Computing

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.

🔗 Computing 🔗 Computing/Computer science

In computer programming, a rope, or cord, is a data structure composed of smaller strings that is used to efficiently store and manipulate a very long string. For example, a text editing program may use a rope to represent the text being edited, so that operations such as insertion, deletion, and random access can be done efficiently.

🔗 Psychology

The McCollough effect is a phenomenon of human visual perception in which colorless gratings appear colored contingent on the orientation of the gratings. It is an aftereffect requiring a period of induction to produce it. For example, if someone alternately looks at a red horizontal grating and a green vertical grating for a few minutes, a black-and-white horizontal grating will then look greenish and a black-and-white vertical grating will then look pinkish. The effect is remarkable because, where time-elapse testing is employed, it has been reported to last up to 2.8 months.

The effect was discovered by American psychologist Celeste McCollough in 1965.

🔗 United States 🔗 Biography 🔗 Women scientists 🔗 Biography/science and academia 🔗 Women's History 🔗 History of Science 🔗 Austria 🔗 Jewish Women 🔗 Biography/Actors and Filmmakers

Hedy Lamarr (), born Hedwig Eva Maria Kiesler (November 9, 1914 – January 19, 2000), was an Austrian-born American actress, inventor and film producer. She was part of 30 films in an acting career spanning 28 years, and co-invented an early version of frequency-hopping spread spectrum.

After a brief early film career in Czechoslovakia, including the controversial Ecstasy (1933), she fled from her husband, a wealthy Austrian ammunition manufacturer, and secretly moved to Paris. Traveling to London, she met Louis B. Mayer, head of Metro-Goldwyn-Mayer (MGM) studio, who offered her a movie contract in Hollywood, where he began promoting her as the "world's most beautiful woman".

She became a star with her performance in Algiers (1938), her first film made in the United States. Her MGM films include Lady of the Tropics (1939), Boom Town (1940), H.M. Pulham, Esq. (1941), and White Cargo (1942). Dismayed with her MGM contract, Lamarr co-founded a new production studio and starred in its films including The Strange Woman (1946), and Dishonored Lady (1947). Her greatest success was as Delilah in Cecil B. DeMille's Samson and Delilah (1949). She also acted on television before the release of her final film, The Female Animal (1958). She was honored with a star on the Hollywood Walk of Fame in 1960.

At the beginning of World War II, Lamarr and composer George Antheil developed a radio guidance system for Allied torpedoes, intended to use frequency-hopping spread spectrum technology to defeat the threat of jamming by the Axis powers. She also helped to improve aviation designs for Howard Hughes while they dated during the war. Although the US Navy did not adopt Lamarr and Antheil's invention until 1957, various spread-spectrum techniques are incorporated into Bluetooth technology and are similar to methods used in legacy versions of Wi-Fi. Recognition of the value of their work resulted in the pair being posthumously inducted into the National Inventors Hall of Fame in 2014.

🔗 Biography 🔗 Biography/science and academia

David J. DeWitt is a computer scientist specializing in database management system research at the Massachusetts Institute of Technology. Prior to moving to MIT, DeWitt was the John P. Morgridge Professor (Emeritus) of Computer Sciences at the University of Wisconsin–Madison. He was also a Technical Fellow at Microsoft, leading the Microsoft Jim Gray Systems Lab at Madison, Wisconsin. Professor DeWitt received a B.A. degree from Colgate University in 1970, and a Ph.D. from the University of Michigan in 1976. He then joined the University of Wisconsin-Madison and started the Wisconsin Database Group, which he led for more than 30 years.

Professor DeWitt is known for his research in the areas of parallel databases, benchmarking, object-oriented databases, and XML databases. He is an elected member of the National Academy of Engineering (1998), and a Fellow of the Association for Computing Machinery.

He received the ACM SIGMOD Innovations Award (now renamed SIGMOD Edgar F. Codd Innovations Award) in 1995 for his contributions to the database systems field. In 2009, ACM recognized the seminal contributions of his Gamma parallel database system project with the ACM Software System Award. Also in 2009, he received the IEEE Emanuel R. Piore Award for his contributions to the database systems field.