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🔗 Military history 🔗 Military history/World War II 🔗 Sweden 🔗 Military history/Nordic military history 🔗 Military history/European military history

En svensk tiger (Swedish: [ɛn ˈsvɛnːsk ˈtǐːɡɛr]) was a slogan and an image that became part of a propaganda campaign in Sweden during World War II. Its goal was to prevent espionage by encouraging secrecy.

🔗 Climate change 🔗 Environment 🔗 Meteorology 🔗 Urban studies and planning

An urban heat island (UHI) is an urban area or metropolitan area that is significantly warmer than its surrounding rural areas due to human activities. The temperature difference is usually larger at night than during the day, and is most apparent when winds are weak. UHI is most noticeable during the summer and winter. The main cause of the urban heat island effect is from the modification of land surfaces. Waste heat generated by energy usage is a secondary contributor. As a population center grows, it tends to expand its area and increase its average temperature. The term heat island is also used; the term can be used to refer to any area that is relatively hotter than the surrounding, but generally refers to human-disturbed areas.

Monthly rainfall is greater downwind of cities, partially due to the UHI. Increases in heat within urban centers increases the length of growing seasons, and decreases the occurrence of weak tornadoes. The UHI decreases air quality by increasing the production of pollutants such as ozone, and decreases water quality as warmer waters flow into area streams and put stress on their ecosystems.

Not all cities have a distinct urban heat island, and the heat island characteristics depend strongly on the background climate of the area in which the city is located. Mitigation of the urban heat island effect can be accomplished through the use of green roofs and the use of lighter-colored surfaces in urban areas, which reflect more sunlight and absorb less heat.

Concerns have been raised about possible contribution from urban heat islands to global warming. While some lines of research did not detect a significant impact, other studies have concluded that heat islands can have measurable effects on climate phenomena at the global scale.

🔗 California 🔗 Computing 🔗 Computing/Networking

Tymnet was an international data communications network headquartered in Cupertino, California that used virtual call packet-switched technology and X.25, SNA/SDLC, BSC and Async interfaces to connect host computers (servers) at thousands of large companies, educational institutions, and government agencies. Users typically connected via dial-up connections or dedicated asynchronous connections.

The business consisted of a large public network that supported dial-up users and a private network that allowed government agencies and large companies (mostly banks and airlines) to build their own dedicated networks. The private networks were often connected via gateways to the public network to reach locations not on the private network. Tymnet was also connected to dozens of other public networks in the United States and internationally via X.25/X.75 gateways.

As the Internet grew and became almost universally accessible in the late 1990s, the need for services such as Tymnet migrated to the Internet style connections, but still had some value in the Third World and for specific legacy roles. However the value of these links continued to decrease, and Tymnet shut down in 2004.

🔗 Mathematics

In geometry, Prince Rupert's cube (named after Prince Rupert of the Rhine) is the largest cube that can pass through a hole cut through a unit cube, i.e. through a cube whose sides have length 1, without splitting the cube into two pieces. Its side length is approximately 6% larger than that of the unit cube through which it passes. The problem of finding the largest square that lies entirely within a unit cube is closely related, and has the same solution.

The original proposition posed by Prince Rupert of the Rhine was that a cube could be passed through a hole made in another cube of the same size without splitting the cube into two pieces.

🔗 Cognitive science

The Sussman anomaly is a problem in artificial intelligence, first described by Gerald Sussman, that illustrates a weakness of noninterleaved planning algorithms, which were prominent in the early 1970s. In the problem, three blocks (labeled A, B, and C) rest on a table. The agent must stack the blocks such that A is atop B, which in turn is atop C. However, it may only move one block at a time. The problem starts with B on the table, C atop A, and A on the table:

However, noninterleaved planners typically separate the goal (stack A atop B atop C) into subgoals, such as:

1. get A atop B
2. get B atop C

Suppose the planner starts by pursuing Goal 1. The straightforward solution is to move C out of the way, then move A atop B. But while this sequence accomplishes Goal 1, the agent cannot now pursue Goal 2 without undoing Goal 1, since both A and B must be moved atop C:

If instead the planner starts with Goal 2, the most efficient solution is to move B. But again, the planner cannot pursue Goal 1 without undoing Goal 2:

The problem was first identified by Sussman as a part of his PhD research. Sussman (and his supervisor, Marvin Minsky) believed that intelligence requires a list of exceptions or tricks, and developed a modular planning system for "debugging" plans. Most modern planning systems can handle this anomaly, but it is still useful for explaining why planning is non-trivial.

🔗 Law 🔗 Statistics

The Howland will forgery trial was a U.S. court case in 1868 to decide Henrietta Howland Robinson's contest of the will of Sylvia Ann Howland. It is famous for the forensic use of mathematics by Benjamin Peirce as an expert witness.

🔗 Transhumanism 🔗 Alternative Views 🔗 Futures studies

American author, inventor and futurist Raymond Kurzweil has become well known for his predictions about artificial intelligence and the human species, mainly concerning the technological singularity. He predicts that Artificial Intelligence would outsmart the human brain in computational capabilities by mid-21st century. His first book, The Age of Intelligent Machines, published in 1990, put forth his theories on the results of the increasing use of technology and predicted the explosive growth in the internet, among other predictions. Later works, 1999's The Age of Spiritual Machines and 2005's The Singularity is Near outlined other theories including the rise of clouds of nano-robots (nanobots) called foglets and the development of Human Body 2.0 and 3.0, whereby nanotechnology is incorporated into many internal organs.

🔗 Philosophy 🔗 Politics 🔗 Socialism 🔗 Philosophy/Social and political philosophy 🔗 Sociology 🔗 Philosophy/Modern philosophy

Marx's theory of alienation describes the estrangement of people from aspects of their essential human nature as a consequence of living in a society structured by private property and wage labour. Developed by the German philosopher Karl Marx and first articulated in his Economic and Philosophic Manuscripts of 1844, the theory is a foundational concept of Marxism. At its core, it posits that under the capitalist mode of production, workers are inevitably separated from the products they create, the activity of production, their fellow human beings, and their own creative potential.

The theory has roots in a long intellectual tradition, particularly in the work of the German idealist philosopher Georg Wilhelm Friedrich Hegel. For Hegel, alienation was a necessary stage in the development of Spirit (Geist), in which it externalises itself in the material world to achieve self-awareness. Marx adapted Hegel's dialectical framework but rejected its idealism, grounding the concept in material reality. Influenced by Ludwig Feuerbach's critique of religious alienation, Marx argued that alienation was not an abstract philosophical condition but a concrete, historical consequence of the capitalist system that could be overcome.

In his analysis, Marx identified four key aspects of alienated labour. First, the worker is alienated from the product of their labour, which is appropriated by the capitalist and confronts the worker as a hostile power. Second, they are alienated from the activity of production itself, which is experienced not as a fulfilling expression of creativity but as coerced, meaningless toil. Third, this leads to alienation from their own human nature, or species-being (Gattungswesen), as free, conscious activity is reduced to a mere means of survival. Finally, the worker is alienated from other people, as social relationships become reified and mediated by market exchange, fostering competition and indifference rather than community.

A long-standing scholarly debate exists over the theory's place in Marx's work, with some arguing he abandoned the humanistic concept in his later, more "scientific" writings. However, many analysts contend that the theory remained a central, unifying concept throughout his intellectual development. They argue that concepts in his mature work, such as the fetishism of commodities in Das Kapital, represent a deeper elaboration of the alienation theme. For Marx, the overcoming of alienation could only be achieved through communism, a revolutionary transformation of society that would abolish private property and allow for the free, collective development of human potential.

🔗 Geology 🔗 Geology/Meteorites

Thokcha (Tibetan: ཐོག་ལྕགས, Wylie: thog lcags; also alternatively Tibetan: གནམ་ལྕགས, Wylie: gnam lcags) are tektites and meteorites which serve as amulets. Typically high in iron content, these are traditionally believed to contain a magical, protective power comparable to Tibetan dzi beads. Most thokcha are made of a copper alloy.

The use of meteoric iron has been common throughout the history of ferrous metallurgy. Historically, thokcha were prized for the metallurgical fabrication of weapons, musical instruments, and sacred tools, such as the phurba. Thokcha are an auspicious addition in the metallurgical fabrication of sacred objects cast from panchaloha.

Writer Robert Beer regards meteoric iron as "the supreme substance for forging the physical representation of the vajra or other iron weapons." It was believed that these amulets had been tempered by the celestial gods before falling to Earth. Beer describes the metal falling from space as a metaphor for "the indivisibility of form and emptiness." Many meteorite fragments can be found in Tibet due to its high altitude and open landscape.

🔗 Psychology

Inductive reasoning aptitude (also called differentiation or inductive learning ability) measures how well a person can identify a pattern within a large amount of data. It involves applying the rules of logic when inferring general principles from a constellation of particulars.

Measurement is generally done in a timed test by showing four pictures or words and asking the test taker to identify which of the pictures or words does not belong in the set. The test taker is shown a large number of sets of various degrees of difficulty. The measurement is made by timing how many of these a person can properly identify in a set period of time. The test resembles the game 'Which of These Is Not Like the Others'.

Inductive reasoning is very useful for scientists, auto mechanics, system integrators, lawyers, network engineers, medical doctors, system administrators and members of all fields where substantial diagnostic or data interpretation work is needed. Inductive reasoning aptitude is also useful for learning a graphical user interface quickly, because highly inductive people are very good at seeing others' categorization schemes. Inductive reasoning aptitude is often counter-productive in fields like sales where tolerance is very important, because highly inductive people tend to be good at seeing faults in others.