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🔗 Technology 🔗 Electronics 🔗 Engineering 🔗 Industrial design

Muntzing is the practice and technique of reducing the components inside an electronic appliance to the minimum required for it to sufficiently function in most operating conditions, reducing design margins above minimum requirements toward zero. The term is named after the man who invented it, Earl "Madman" Muntz, a car and electronics salesman, who was not formally educated or trained in any science or engineering discipline.

In the 1940s and 1950s, television receivers were relatively new to the consumer market, and were more complex pieces of equipment than the radios which were then in popular use. TVs often contained upwards of 30 vacuum tubes, as well as transformers, rheostats, and other electronics. The consequence of high cost was high sales pricing, limiting potential for high-volume sales. Muntz expressed suspicion of complexity in circuit designs, and determined through simple trial and error that he could remove a significant number of electronic components from a circuit design and still end up with a monochrome TV that worked sufficiently well in urban areas, close to transmission towers where the broadcast signal was strong. He carried a pair of wire clippers, and when he felt that one of his builders was overengineering a circuit, he would begin snipping out some of the electronics components. When the TV stopped functioning, he would have the technician reinsert the last removed part. He would repeat the snipping in other portions of the circuit until he was satisfied in his simplification efforts, and then leave the TV as it was without further testing in more adverse conditions for signal reception.

As a result, he reduced his costs and increased his profits at the expense of poorer performance at locations more distant from urban centers. He reasoned that population density was higher in and near the urban centers where the TVs would work, and lower further out where the TVs would not work, so the Muntz TVs were adequate for a very large fraction of his customers. And for those further out, where the Muntz TVs did not work, those could be returned at the customer's additional effort and expense, and not Muntz's. He focused less resources in the product, intentionally accepting bare minimum performance quality, and focused more resources on advertising and sales promotions.

🔗 Mathematics 🔗 Physics

An amplituhedron is a geometric structure introduced in 2013 by Nima Arkani-Hamed and Jaroslav Trnka. It enables simplified calculation of particle interactions in some quantum field theories. In planar N = 4 supersymmetric Yang–Mills theory, also equivalent to the perturbative topological B model string theory in twistor space, an amplituhedron is defined as a mathematical space known as the positive Grassmannian.

Amplituhedron theory challenges the notion that spacetime locality and unitarity are necessary components of a model of particle interactions. Instead, they are treated as properties that emerge from an underlying phenomenon.

The connection between the amplituhedron and scattering amplitudes is at present a conjecture that has passed many non-trivial checks, including an understanding of how locality and unitarity arise as consequences of positivity. Research has been led by Nima Arkani-Hamed. Edward Witten described the work as "very unexpected" and said that "it is difficult to guess what will happen or what the lessons will turn out to be".

🔗 Medicine 🔗 Biology

Closed-eye hallucinations and closed-eye visualizations (CEV) are a distinct class of hallucination. These types of hallucinations generally only occur when one's eyes are closed or when one is in a darkened room. They can be a form of phosphene. Some people report closed-eye hallucinations under the influence of psychedelics. These are reportedly of a different nature than the "open-eye" hallucinations of the same compounds. Similar hallucinations that occur due to loss of vision are called visual release hallucinations.

🔗 Mathematics

Modern Arabic mathematical notation is a mathematical notation based on the Arabic script, used especially at pre-university levels of education. Its form is mostly derived from Western notation, but has some notable features that set it apart from its Western counterpart. The most remarkable of those features is the fact that it is written from right to left following the normal direction of the Arabic script. Other differences include the replacement of the Greek and Latin alphabet letters for symbols with Arabic letters and the use of Arabic names for functions and relations.

🔗 Philosophy 🔗 Philosophy/Philosophical literature 🔗 Books 🔗 Philosophy/Modern philosophy 🔗 Japan 🔗 Philosophy/Eastern philosophy

The "Dokkōdō" (Japanese: 獨行道) ("The Path of Aloneness", "The Way to Go Forth Alone", or "The Way of Walking Alone"), is a short work written by Miyamoto Musashi a week before he died in 1645. It consists of 21 precepts. "Dokkodo" was largely composed on the occasion of Musashi giving away his possessions in preparation for death, and was dedicated to his favorite disciple, Terao Magonojō (to whom the earlier Go rin no sho [The Book of Five Rings] had also been dedicated), who took them to heart. "Dokkōdō" expresses a stringent, honest, and ascetic view of life.

The 21 precepts of Dokkodo:

1. Accept everything just the way it is.

2. Do not seek pleasure for its own sake.

3. Do not, under any circumstances, depend on a partial feeling.

4. Think lightly of yourself and deeply of the world.

5. Be detached from desire your whole life long.

6. Do not regret what you have done.

7. Never be jealous.

8. Never let yourself be saddened by a separation.

9. Resentment and complaint are appropriate neither for oneself or others.

10. Do not let yourself be guided by the feeling of lust or love.

11. In all things have no preferences.

12. Be indifferent to where you live.

13. Do not pursue the taste of good food.

14. Do not hold on to possessions you no longer need.

15. Do not act following customary beliefs.

16. Do not collect weapons or practice with weapons beyond what is useful.

17. Do not fear death.

18. Do not seek to possess either goods or fiefs for your old age.

19. Respect Buddha and the gods without counting on their help.

20. You may abandon your own body but you must preserve your honour.

21. Never stray from the Way.

🔗 Physics 🔗 Elements 🔗 Elements/Isotope 🔗 Chemistry

In nuclear physics, the island of stability is a predicted set of isotopes of superheavy elements that may have considerably longer half-lives than known isotopes of these elements. It is predicted to appear as an "island" in the chart of nuclides, separated from known stable and long-lived primordial radionuclides. Its theoretical existence is attributed to stabilizing effects of predicted "magic numbers" of protons and neutrons in the superheavy mass region.

Several predictions have been made regarding the exact location of the island of stability, though it is generally thought to center near copernicium and flerovium isotopes in the vicinity of the predicted closed neutron shell at N = 184. These models strongly suggest that the closed shell will confer further stability towards fission and alpha decay. While these effects are expected to be greatest near atomic number Z = 114 and N = 184, the region of increased stability is expected to encompass several neighboring elements, and there may also be additional islands of stability around heavier nuclei that are doubly magic (having magic numbers of both protons and neutrons). Estimates of the stability of the elements on the island are usually around a half-life of minutes or days; some estimates predict half-lives of millions of years.

Although the nuclear shell model predicting magic numbers has existed since the 1940s, the existence of long-lived superheavy nuclides has not been definitively demonstrated. Like the rest of the superheavy elements, the nuclides on the island of stability have never been found in nature; thus, they must be created artificially in a nuclear reaction to be studied. Scientists have not found a way to carry out such a reaction, for it is likely that new types of reactions will be needed to populate nuclei near the center of the island. Nevertheless, the successful synthesis of superheavy elements up to Z = 118 (oganesson) with up to 177 neutrons demonstrates a slight stabilizing effect around elements 110 to 114 that may continue in unknown isotopes, supporting the existence of the island of stability.

🔗 Film 🔗 Film/Filmmaking 🔗 Photography 🔗 Photography/History of photography

The Zone System is a photographic technique for determining optimal film exposure and development, formulated by Ansel Adams and Fred Archer. Adams described the Zone System as "[...] not an invention of mine; it is a codification of the principles of sensitometry, worked out by Fred Archer and myself at the Art Center School in Los Angeles, around 1939–40."

The technique is based on the late 19th century sensitometry studies of Hurter and Driffield. The Zone System provides photographers with a systematic method of precisely defining the relationship between the way they visualize the photographic subject and the final results. Although it originated with black-and-white sheet film, the Zone System is also applicable to roll film, both black-and-white and color, negative and reversal, and to digital photography.

🔗 Medicine 🔗 Iran 🔗 History of Science 🔗 Middle Ages 🔗 Islam 🔗 Middle Ages/History 🔗 Turkey

A bimaristan (Persian: بيمارستان‎, romanized: bīmārestān; Arabic: بِيْمَارِسْتَان‎, romanized: bīmāristān), also known as dar al-shifa (also darüşşifa in Turkish) or simply maristan, is a hospital in the historic Islamic world.

🔗 Pharmacology

The oligodynamic effect (from Greek oligos "few", and dynamis "force") is a biocidal effect of metals, especially heavy metals, that occurs even in low concentrations.

In modern times, the effect was observed by Karl Wilhelm von Nägeli, although he did not identify the cause. Scholarly texts from ancient India promoted the use of brass and silver in ritual cleansing practice as well as in consumption of food and drink. The ancient Indian medical text Sushruta Samhita promoted the use of specific metals in surgical procedures as a measure to prevent infection. Brass doorknobs and silverware both exhibit this effect to an extent.

🔗 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.