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🔗 Cassowary

🔗 Australia 🔗 Birds

Casuarius is a genus of birds in the order Casuariiformes, whose members are the cassowaries (Tok Pisin: muruk, Indonesian: kasuari). It is classified as a ratite (flightless bird without a keel on its sternum bone) and is native to the tropical forests of New Guinea (Papua New Guinea and East Indonesia), Aru Islands (Maluku), and northeastern Australia.

Three species are extant: The most common, the southern cassowary, is the third-tallest and second-heaviest living bird, smaller only than the ostrich and emu. The other two species are represented by the northern cassowary and the dwarf cassowary; the northern cassowary is the most recently discovered and the most threatened. A fourth but extinct species is represented by the pygmy cassowary.

Cassowaries feed mainly on fruit, although all species are truly omnivorous and take a range of other plant foods, including shoots and grass seeds, in addition to fungi, invertebrates, and small vertebrates. Cassowaries are very wary of humans, but if provoked, they are capable of inflicting serious, even fatal, injuries to both dogs and people. The cassowary has often been labeled "the world's most dangerous bird".

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🔗 HP Saturn

🔗 Computing 🔗 Computing/Computer hardware

The Saturn family of 4-bit (datapath) microprocessors was developed by Hewlett-Packard in the 1980s first for the HP-71B handheld computer and then later for various HP calculators (starting with the HP-18C). It succeeded the Nut family of processors used in earlier calculators. The original Saturn chip was first used in the HP-71B hand-held BASIC-programmable computer, introduced in 1984. Later models of the family powered the popular HP 48 series of calculators. The HP48SX and HP48S were the last models to use genuine Saturn processors manufactured by HP. Later calculator models used Saturn processors manufactured by NEC. The HP 49 series initially used the Saturn CPU as well, until the NEC fab could no longer manufacture the processor for technical reasons in 2003. Therefore, starting with the HP 49g+ model in 2003, the calculators switched to a Samsung S3C2410 processor with an ARM920T core (part of the ARMv4T architecture) which ran an emulator of the Saturn hardware in software. In 2000, the HP 39G and HP 40G were the last calculators introduced based on the actual NEC fabricated Saturn hardware. The last calculators based on the Saturn emulator were the HP 39gs, HP 40gs and HP 50g in 2006, as well as the 2007 revision of the hp 48gII. The HP 50g, the last calculator utilizing this emulator, was discontinued in 2015 when Samsung stopped producing the ARM processor on which it was based.

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🔗 Karelian Question

🔗 International relations 🔗 Soviet Union 🔗 Russia 🔗 Russia/politics and law of Russia 🔗 Finland

The Karelian question or Karelian issue (Finnish: Karjala-kysymys, Swedish: Karelska frågan) is a dispute in Finnish politics over whether to try to regain control over eastern Finnish Karelia and other territories ceded to the Soviet Union in the Winter War and the Continuation War. Despite the name "Karelian question", the term may refer also to the return of Petsamo, ceded parts of Salla and Kuusamo, and four islands in the Gulf of Finland. Sometimes the phrase "debate on the return of the ceded territories" (luovutettujen alueiden palautuskeskustelu, Swedish: debatten om tillbakalämningen av de avträdda territorierna) is used. The Karelian question remains a matter of public debate rather than a political issue.

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🔗 List of most expensive video games to develop

🔗 Video games 🔗 Lists

The following is a list of the most expensive video games ever developed, with a minimum total cost of US$50 million and sorted by the total cost adjusted for inflation. Most game budgets are not disclosed, so this list is not indicative of industry trends.

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🔗 2000-Watt Society

🔗 Climate change 🔗 Environment 🔗 Switzerland 🔗 Urban studies and planning 🔗 Energy

The 2000-watt society is an environmental vision, first introduced in 1998 by the Swiss Federal Institute of Technology in Zürich (ETH Zurich), which pictures the average First World citizen reducing their overall average primary energy usage rate to no more than 2,000 watts (i.e. 2 kWh per hour or 48 kWh per day) by the year 2050, without lowering their standard of living.

The concept addresses not only personal or household energy use, but the total for the whole society, including embodied energy, divided by the population.

Two thousand watts is approximately the current world average rate of total primary energy use. This compared, in 2008, to averages of around 6,000 watts in western Europe, 12,000 watts in the United States, 1,500 watts in China, 1,000 watts in India, 500 watts in South Africa and only 300 watts in Bangladesh. Switzerland itself, then using an average of around 5,000 watts, was last a 2000-watt society in the 1960s.

It is further envisaged that the use of carbon-based fuels would be ultimately cut to no more than 500 watts per person within 50 to 100 years.

The vision was developed in response to concerns about climate change, energy security, and the future availability of energy supplies. It is supported by the Swiss Federal Office of Energy, the Association of Swiss Architects and Engineers, and other bodies.

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🔗 History of the Monte Carlo method

🔗 Computing 🔗 Computer science 🔗 Mathematics 🔗 Physics 🔗 Statistics

Monte Carlo methods, or Monte Carlo experiments, are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results. The underlying concept is to use randomness to solve problems that might be deterministic in principle. They are often used in physical and mathematical problems and are most useful when it is difficult or impossible to use other approaches. Monte Carlo methods are mainly used in three problem classes: optimization, numerical integration, and generating draws from a probability distribution.

In physics-related problems, Monte Carlo methods are useful for simulating systems with many coupled degrees of freedom, such as fluids, disordered materials, strongly coupled solids, and cellular structures (see cellular Potts model, interacting particle systems, McKean–Vlasov processes, kinetic models of gases).

Other examples include modeling phenomena with significant uncertainty in inputs such as the calculation of risk in business and, in mathematics, evaluation of multidimensional definite integrals with complicated boundary conditions. In application to systems engineering problems (space, oil exploration, aircraft design, etc.), Monte Carlo–based predictions of failure, cost overruns and schedule overruns are routinely better than human intuition or alternative "soft" methods.

In principle, Monte Carlo methods can be used to solve any problem having a probabilistic interpretation. By the law of large numbers, integrals described by the expected value of some random variable can be approximated by taking the empirical mean (a.k.a. the sample mean) of independent samples of the variable. When the probability distribution of the variable is parameterized, mathematicians often use a Markov chain Monte Carlo (MCMC) sampler. The central idea is to design a judicious Markov chain model with a prescribed stationary probability distribution. That is, in the limit, the samples being generated by the MCMC method will be samples from the desired (target) distribution. By the ergodic theorem, the stationary distribution is approximated by the empirical measures of the random states of the MCMC sampler.

In other problems, the objective is generating draws from a sequence of probability distributions satisfying a nonlinear evolution equation. These flows of probability distributions can always be interpreted as the distributions of the random states of a Markov process whose transition probabilities depend on the distributions of the current random states (see McKean–Vlasov processes, nonlinear filtering equation). In other instances we are given a flow of probability distributions with an increasing level of sampling complexity (path spaces models with an increasing time horizon, Boltzmann–Gibbs measures associated with decreasing temperature parameters, and many others). These models can also be seen as the evolution of the law of the random states of a nonlinear Markov chain. A natural way to simulate these sophisticated nonlinear Markov processes is to sample multiple copies of the process, replacing in the evolution equation the unknown distributions of the random states by the sampled empirical measures. In contrast with traditional Monte Carlo and MCMC methodologies, these mean-field particle techniques rely on sequential interacting samples. The terminology mean field reflects the fact that each of the samples (a.k.a. particles, individuals, walkers, agents, creatures, or phenotypes) interacts with the empirical measures of the process. When the size of the system tends to infinity, these random empirical measures converge to the deterministic distribution of the random states of the nonlinear Markov chain, so that the statistical interaction between particles vanishes.

Despite its conceptual and algorithmic simplicity, the computational cost associated with a Monte Carlo simulation can be staggeringly high. In general the method requires many samples to get a good approximation, which may incur an arbitrarily large total runtime if the processing time of a single sample is high. Although this is a severe limitation in very complex problems, the embarrassingly parallel nature of the algorithm allows this large cost to be reduced (perhaps to a feasible level) through parallel computing strategies in local processors, clusters, cloud computing, GPU, FPGA, etc.

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🔗 An account of travel to the five Indian kingdoms – 723 CE

🔗 Korea 🔗 Buddhism

Wang ocheonchukguk jeon (Korean pronunciation: [waːŋotɕʰʌntɕʰukk͈uktɕ͈ʌn]; pinyin: wǎng wǔ tiānzhú guó zhuàn; "An account of travel to the five Indian kingdoms") is a travelogue by Buddhist monk Hyecho, who traveled from Korea to India, in the years 723 - 727/728 CE.

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🔗 Andrée's Arctic Balloon Expedition

🔗 Aviation 🔗 Norway 🔗 Arctic 🔗 Sweden

Andrée's Arctic balloon expedition of 1897 was an effort to reach the North Pole in which all three Swedish expedition members – S. A. Andrée, Knut Frænkel, and Nils Strindberg – perished. Andrée, the first Swedish balloonist, proposed a voyage by hydrogen balloon from Svalbard to either Russia or Canada, which was to pass, with luck, straight over the North Pole on the way. The scheme was received with patriotic enthusiasm in Sweden, a northern nation that had fallen behind in the race for the North Pole.

Andrée ignored many early signs of the dangers associated with his balloon plan. Being able to steer the balloon to some extent was essential for a safe journey, but there was much evidence that the drag-rope steering technique he had invented was ineffective. Worse, the polar balloon Örnen (Eagle) was delivered directly to Svalbard from its manufacturer in Paris without being tested. When measurements showed it to be leaking more than expected, Andrée failed to acknowledge the risk.

After Andrée, Strindberg, and Frænkel lifted off from Svalbard in July 1897, the balloon lost hydrogen quickly and crashed on the pack ice after only two days. The explorers were unhurt but faced a grueling trek back south across the drifting icescape. Inadequately clothed, equipped, and prepared, and shocked by the difficulty of the terrain, they did not make it to safety. As the Arctic winter closed in on them in October, the group ended up exhausted on the deserted Kvitøya (White Island) in Svalbard and died there. For 33 years the fate of the expedition remained one of the unsolved riddles of the Arctic. The chance discovery in 1930 of the expedition's last camp created a media sensation in Sweden, where the dead men had been mourned and idolized.

Andrée's motives and mindset have been the subject of extensive fictional and historical discussion, particularly inspired by his apparent foolhardiness. An early example is Per Olof Sundman's fictionalized bestseller novel of 1967, The Flight of the Eagle, which portrays Andrée as weak and cynical, at the mercy of his sponsors and the media. Modern writers have been generally critical of Andrée.

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🔗 2022 Russian businessmen mystery deaths

🔗 Russia 🔗 Crime 🔗 Death

The 2022 Russian businessmen mystery deaths are a series of unusual deaths of Russian-connected businessmen in 2022. Most of the deaths were officially declared to be suicides, but a number of commentators have suggested that the circumstances of the suicides appear to be suspicious and may have been staged.

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🔗 Countersteering

🔗 Cycling 🔗 Motorcycling

Countersteering is used by single-track vehicle operators, such as cyclists and motorcyclists, to initiate a turn toward a given direction by momentarily steering counter to the desired direction ("steer left to turn right"). To negotiate a turn successfully, the combined center of mass of the rider and the single-track vehicle must first be leaned in the direction of the turn, and steering briefly in the opposite direction causes that lean. The rider's action of countersteering is sometimes referred to as "giving a steering command".: 15 

The scientific literature does not provide a clear and comprehensive definition of countersteering. In fact, "a proper distinction between steer torque and steer angle ... is not always made."

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