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🔗 Spaceflight 🔗 Rocketry

Black Arrow, officially capitalised BLACK ARROW, was a British satellite carrier rocket. Developed during the 1960s, it was used for four launches between 1969 and 1971. Its final flight was the first and only successful orbital launch to be conducted by the United Kingdom, and placed the Prospero satellite into low Earth orbit.

Black Arrow originated from studies by the Royal Aircraft Establishment for carrier rockets based on the Black Knight rocket, with the project being authorised in 1964. It was initially developed by Saunders-Roe, and later Westland Aircraft as the result of a merger.

Black Arrow was a three-stage rocket, fuelled by RP-1 paraffin (kerosene) and high test peroxide, a concentrated form of hydrogen peroxide (85% hydrogen peroxide + 15% water). It was retired after only four launches in favour of using American Scout rockets, which the Ministry of Defence calculated to be cheaper than maintaining the Black Arrow programme.

🔗 Technology

A planimeter, also known as a platometer, is a measuring instrument used to determine the area of an arbitrary two-dimensional shape.

🔗 International relations 🔗 History 🔗 Military history 🔗 Africa 🔗 Europe 🔗 Military history/African military history 🔗 British Empire 🔗 Military history/World War II 🔗 Colonialism 🔗 Countering systemic bias

The Scramble for Africa, also called the Partition of Africa or the Conquest of Africa, was the invasion, occupation, division, and colonisation of African territory by European powers during a short period known to historians as the New Imperialism (between 1881 and 1914). In 1870, only 10 percent of Africa was under formal European control; by 1914 this had increased to almost 90 percent of the continent, with only Ethiopia (Abyssinia), the Dervish state (a portion of present-day Somalia) and Liberia still being independent. There were multiple motivations for European colonizers, including desire for valuable resources available throughout the continent, the quest for national prestige, tensions between pairs of European powers, religious missionary zeal and internal African native politics.

The Berlin Conference of 1884, which regulated European colonisation and trade in Africa, is usually referred to as the ultimate point of the Scramble for Africa. Consequent to the political and economic rivalries among the European empires in the last quarter of the 19th century, the partitioning, or splitting up of Africa was how the Europeans avoided warring amongst themselves over Africa. The later years of the 19th century saw the transition from "informal imperialism" by military influence and economic dominance, to direct rule, bringing about colonial imperialism.

🔗 Europe/ESA

🔗 Spaceflight

NASA Extreme Environment Mission Operations, or NEEMO, is a NASA analog mission that sends groups of astronauts, engineers and scientists to live in Aquarius underwater laboratory, the world's only undersea research station, for up to three weeks at a time in preparation for future space exploration.

Aquarius is an underwater habitat 3.5 miles (5.6 km) off Key Largo, Florida, in the Florida Keys National Marine Sanctuary. It is deployed on the ocean floor next to deep coral reefs 62 feet (19 m) below the surface.

NASA has used it since 2001 for a series of space exploration simulation missions, usually lasting 7 to 14 days, with space research mainly conducted by international astronauts. The mission had cost about 500 million U.S. dollars. The crew members are called aquanauts (as they live underwater at depth pressure for a period equal to or greater than 24 continuous hours without returning to the surface), and they perform EVAs in the underwater environment. A technique known as saturation diving allows the aquanauts to live and work underwater for days or weeks at a time. After twenty four hours underwater at any depth, the human body becomes saturated with dissolved gas. With saturation diving, divers can accurately predict exactly how much time they need to decompress before returning to the surface. This information limits the risk of decompression sickness. By living in the Aquarius habitat and working at the same depth on the ocean floor, NEEMO crews are able to remain underwater for the duration of their mission.

For NASA, the Aquarius habitat and its surroundings provide a convincing analog for space exploration. Much like space, the undersea world is a hostile, alien place for humans to live. NEEMO crew members experience some of the same challenges there that they would on a distant asteroid, planet (i.e. Mars) or Moon. During NEEMO missions, the aquanauts are able to simulate living on a spacecraft and test spacewalk techniques for future space missions. Working in space and underwater environments requires extensive planning and sophisticated equipment. The underwater condition has the additional benefit of allowing NASA to "weight" the aquanauts to simulate different gravity environments.

Until 2012, Aquarius was owned by the National Oceanic and Atmospheric Administration (NOAA) and operated by the National Undersea Research Center (NURC) at the University of North Carolina–Wilmington as a marine biology study base.

Since 2013, Aquarius is owned by Florida International University (FIU). As part of the FIU Marine Education and Research Initiative, the Medina Aquarius Program is dedicated to the study and preservation of marine ecosystems worldwide and is enhancing the scope and impact of FIU on research, educational outreach, technology development, and professional training. At the heart of the program is the Aquarius Reef Base.

🔗 Computing 🔗 Computer science

A one-instruction set computer (OISC), sometimes called an ultimate reduced instruction set computer (URISC), is an abstract machine that uses only one instruction – obviating the need for a machine language opcode. With a judicious choice for the single instruction and given infinite resources, an OISC is capable of being a universal computer in the same manner as traditional computers that have multiple instructions. OISCs have been recommended as aids in teaching computer architecture and have been used as computational models in structural computing research.

🔗 Economics 🔗 Robotics 🔗 Game theory

Mechanism design is a field in economics and game theory that takes an objectives-first approach to designing economic mechanisms or incentives, toward desired objectives, in strategic settings, where players act rationally. Because it starts at the end of the game, then goes backwards, it is also called reverse game theory. It has broad applications, from economics and politics (markets, auctions, voting procedures) to networked-systems (internet interdomain routing, sponsored search auctions).

Mechanism design studies solution concepts for a class of private-information games. Leonid Hurwicz explains that 'in a design problem, the goal function is the main "given", while the mechanism is the unknown. Therefore, the design problem is the "inverse" of traditional economic theory, which is typically devoted to the analysis of the performance of a given mechanism.' So, two distinguishing features of these games are:

• that a game "designer" chooses the game structure rather than inheriting one
• that the designer is interested in the game's outcome

The 2007 Nobel Memorial Prize in Economic Sciences was awarded to Leonid Hurwicz, Eric Maskin, and Roger Myerson "for having laid the foundations of mechanism design theory".

🔗 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.

🔗 Iran 🔗 Cities

Ramsar (Persian: رامسر, also Romanized as Rámsar and Ránsar; formerly, Sakht Sar) is the capital of Ramsar County, Mazandaran Province, Iran. In 2012 its population was 33,018, in 9,421 families.

Ramsar lies on the coast of the Caspian Sea. It was also known as Sakhtsar in the past. The climate of Ramsar is hot and humid in summer and mild in winter. The proximity of the forest and the sea in this city has given a special beauty to this city and this attracts tourists in all seasons. Ramsar has an airport. The city of Ramsar was a small village in western Mazandaran until the Qajar period, and during the first Pahlavi period, with the rule of Reza Shah and with the support of the government, it became a beautiful city with many tourist facilities.

Ramsar is the westernmost county and city in Mazandaran. It borders the Caspian Sea to the north, Gilan province to the west, Qazvin Province to the south, and Tonekabon to the east.

🔗 United States 🔗 Film 🔗 Library of Congress 🔗 Film/American cinema 🔗 United States/Film - American cinema 🔗 Film/Core

The Conversation is a 1974 American mystery thriller film written, produced and directed by Francis Ford Coppola and starring Gene Hackman with supporting roles by John Cazale, Allen Garfield, Cindy Williams, Frederic Forrest, Harrison Ford, Teri Garr and Robert Duvall.

The plot revolves around a surveillance expert and the moral dilemma he faces when his recordings reveal a potential murder. Coppola cited the 1966 film Blowup as a key influence. However, since the film was released to theaters just a few months before Richard Nixon resigned as President, he felt that audiences interpreted the film to be a reaction to the Watergate scandal. The Conversation has won critical acclaim and multiple accolades, including the Grand Prix du Festival International du Film, the highest honor at the 1974 Cannes Film Festival. It was nominated for three Academy Awards in 1974 and lost Best Picture to The Godfather Part II, another Francis Ford Coppola film. In 1995, it was selected for preservation in the National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant".