Have a deep view into what people are curious about.

🔗 Biography 🔗 Africa 🔗 BBC 🔗 Africa/Republic of the Congo

Guy Goma (born 1969) is a Congolese-French business studies graduate from Brazzaville in the Republic of the Congo who was accidentally interviewed live on BBC News 24, a UK television news station, on Monday 8 May 2006. Goma was mistaken for technology expert Guy Kewney when he attended the BBC for a job interview and was brought onto a BBC special regarding the case Apple Corps v Apple Computer to provide insight on a subject he knew little about.

Goma became well known for the incident, which is noted as a memorable TV moment.

🔗 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.

🔗 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.

🔗 Russia 🔗 China

"China's final warning" (Russian: Последнее китайское предупреждение) is a Russian proverb meaning a warning that carries no real consequences.

🔗 Numismatics 🔗 Numismatics/Cryptocurrency 🔗 Cryptocurrency

A proof-of-work (PoW) system (or protocol, or function) is a consensus mechanism. It deters denial-of-service attacks and other service abuses such as spam on a network by requiring some work from the service requester, usually meaning processing time by a computer. The concept was invented by Cynthia Dwork and Moni Naor as presented in a 1993 journal article. The term "proof of work" was first coined and formalized in a 1999 paper by Markus Jakobsson and Ari Juels.

A key feature of these schemes is their asymmetry: the work must be moderately hard (yet feasible) on the requester side but easy to check for the service provider. This idea is also known as a CPU cost function, client puzzle, computational puzzle, or CPU pricing function. It is distinct from a CAPTCHA, which is intended for a human to solve quickly, while being difficult to solve for a computer.

🔗 Computing 🔗 Computing/Software

Whitespace is an esoteric programming language developed by Edwin Brady and Chris Morris at the University of Durham (also developers of the Kaya and Idris programming languages). It was released on 1 April 2003 (April Fool's Day). Its name is a reference to whitespace characters. Unlike most programming languages, which ignore or assign little meaning to most whitespace characters, the Whitespace interpreter ignores any non-whitespace characters. Only spaces, tabs and linefeeds have meaning. A consequence of this property is that a Whitespace program can easily be contained within the whitespace characters of a program written in another language, except possibly in languages which depend on spaces for syntax validity such as Python, making the text a polyglot.

The language itself is an imperative stack-based language. The virtual machine on which the programs run has a stack and a heap. The programmer is free to push arbitrary-width integers onto the stack (currently there is no implementation of floating point numbers) and can also access the heap as a permanent store for variables and data structures.

🔗 Mathematics 🔗 Statistics 🔗 Psychology

Accuracy and precision are two measures of observational error. Accuracy is how close a given set of measurements (observations or readings) are to their true value. Precision is how close the measurements are to each other.

The International Organization for Standardization (ISO) defines a related measure: trueness, "the closeness of agreement between the arithmetic mean of a large number of test results and the true or accepted reference value."

While precision is a description of random errors (a measure of statistical variability), accuracy has two different definitions:

1. More commonly, a description of systematic errors (a measure of statistical bias of a given measure of central tendency, such as the mean). In this definition of "accuracy", the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both, or neither. This concept corresponds to ISO's trueness.
2. A combination of both precision and trueness, accounting for the two types of observational error (random and systematic), so that high accuracy requires both high precision and high trueness. This usage corresponds to ISO's definition of accuracy (trueness and precision).

🔗 North America

The Alcoa 50,000 ton forging press is a heavy press operated at Howmet Aerospace's Cleveland Operations. It was built as part of the Heavy Press Program by the United States Air Force. It was manufactured by Mesta Machinery of West Homestead, Pennsylvania, and began operation on May 5, 1955.

Alcoa ran the plant from the time of its construction, and purchased it outright in 1982. In 2008, cracks were discovered in the press, which had to be shut down for safety reasons. Repairs, originally estimated at a cost of $68 million (equivalent to $81.04 million in 2019), cost a total of $100 million, and were completed in early 2012.

🔗 Books 🔗 Food and drink

This Is the Boke of Cokery, or The Boke of Cokery, is believed to be the first cookery book printed in English. The name of the author is unknown. It was printed and published by Richard Pynson in 1500. The book remained in print for many years in the 16th century, but was superseded and forgotten by the 18th. The only known surviving copy of the book is in the possession of the Marquess of Bath at Longleat House, Wiltshire.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Classical Greece and Rome 🔗 Military history/Classical warfare

Polybolos, meaning "multi thrower" in Greek, was an ancient Greek repeating ballista reputedly invented by Dionysius of Alexandria, a 3rd-century BC Greek engineer at the Rhodes arsenal, and used in antiquity.

Philo of Byzantium encountered and described a weapon similar to the polybolos, a catapult that like a modern machine gun could fire again and again without a need to reload. Philo left a detailed description of the gears that powered its chain drive, the oldest known application of such a mechanism, and that placed bolt after bolt into its firing slot.