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πŸ”— Monobloc chair

πŸ”— Home Living

The Monobloc (From mono- (β€œone”) + bloc (β€œblock”), meaning an object forged in a single piece) chair is a lightweight stackable polypropylene chair, usually white in colour, often described as the world's most common plastic chair.

Based on original designs by the Canadian designer D.C. Simpson in 1946, variants of the one-piece plastic chair went into production with Allibert Group and Grosfillex Group in the 1970s. They were inspired by the Chair Universal 4867 design by Joe Colombo in 1965, but no patents were filed for a monobloc chair design. Since then, millions have been manufactured in countries including Russia, Taiwan, Australia, Mexico, the United States, Italy, France, Germany, Morocco, Turkey, Israel, India and China. The Monobloc chair is named because it is injection moulded from thermoplastic polypropylene, the granules being heated to about 220 degrees Celsius, and the melt injected into a mold. The gate of the mould is usually located in the seat, so ensuring smooth flow to all parts of the tool.

Close to a billion Monoblocs have been sold in Europe alone, with one Italian manufacturer producing over ten million a year. Many design variants of the basic idea exist. The chairs cost approximately $3.50 to produce, making them affordable across the world. The stackable design aids setting up large gatherings and storage of the chairs afterwards. In developing countries with high population growth, monoblocs are used to seat thousands of church attendees at a time. Social theorist Ethan Zuckerman describes the chair as having achieved a cultural global ubiquity.

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πŸ”— A*

πŸ”— Computing πŸ”— Computer science πŸ”— Mathematics

A* (pronounced "A-star") is a graph traversal and path search algorithm, which is often used in computer science due to its completeness, optimality, and optimal efficiency. One major practical drawback is its O ( b d ) {\displaystyle O(b^{d})} space complexity, as it stores all generated nodes in memory. Thus, in practical travel-routing systems, it is generally outperformed by algorithms which can pre-process the graph to attain better performance, as well as memory-bounded approaches; however, A* is still the best solution in many cases.

Peter Hart, Nils Nilsson and Bertram Raphael of Stanford Research Institute (now SRI International) first published the algorithm in 1968. It can be seen as an extension of Edsger Dijkstra's 1959 algorithm. A* achieves better performance by using heuristics to guide its search.

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  • "A*" | 2019-08-10 | 50 Upvotes 6 Comments

πŸ”— Free Speech Zone

πŸ”— United States πŸ”— Freedom of speech

Free speech zones (also known as First Amendment zones, free speech cages, and protest zones) are areas set aside in public places for the purpose of political protesting. The First Amendment to the United States Constitution states that "Congress shall make no law ... abridging ... the right of the people peaceably to assemble, and to petition the Government for a redress of grievances." The existence of free speech zones is based on U.S. court decisions stipulating that the government may reasonably regulate the time, place, and manner – but not content – of expression.

The Supreme Court has developed a four-part analysis to evaluate the constitutionality of time, place and manner (TPM) restrictions. To pass muster under the First Amendment, TPM restrictions must be neutral with respect to content, be narrowly drawn, serve a significant government interest, and leave open alternative channels of communication. Application of this four-part analysis varies with the circumstances of each case, and typically requires lower standards for the restriction of obscenity and fighting words.

Free speech zones have been used at a variety of political gatherings. The stated purpose of free speech zones is to protect the safety of those attending the political gathering, or for the safety of the protesters themselves. Critics, however, suggest that such zones are "Orwellian", and that authorities use them in a heavy-handed manner to censor protesters by putting them literally out of sight of the mass media, hence the public, as well as visiting dignitaries. Though authorities generally deny specifically targeting protesters, on a number of occasions, these denials have been contradicted by subsequent court testimony. The American Civil Liberties Union (ACLU) has filed, with various degrees of success and failure, a number of lawsuits on the issue.

Though free speech zones existed prior to the Presidency of George W. Bush, it was during Bush's presidency that their scope was greatly expanded. These zones continued through the presidency of Barack Obama; he signed a bill in 2012 that expanded the power of the Secret Service to restrict speech and make arrests.

Many colleges and universities earlier instituted free speech zone rules during the Vietnam-era protests of the 1960s and 1970s. In recent years, a number of them have revised or removed these restrictions following student protests and lawsuits.

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πŸ”— Zellige

πŸ”— Visual arts πŸ”— Morocco

Zellige (Arabic:Β [zˈliΚ‘]; Arabic: Ψ§Ω„Ψ²Ω„ΩŠΨ¬β€Ž; also zelige or zellij or zileej) is mosaic tilework made from individually chiseled geometric tiles set into a plaster base. This form of Islamic art is one of the main characteristics of Moroccan architecture. It consists of geometrically patterned mosaics, used to ornament walls, ceilings, fountains, floors, pools and tables. The Moroccan traditional patterns and styles are found inside famous buildings such as Al-Qarawiyyin Mosque in Fez, the Alhambra in Granada, Spain, the Great Mosque of Cordoba, the Ben Youssef Madrasa in Marrakech, and the Hassan II mosque in Casablanca, which adds a new color palette with traditional designs.

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πŸ”— Woo! Yeah!

πŸ”— Electronic music πŸ”— R&B and Soul Music

Woo! Yeah! is a drum break that includes James Brown's ("Woo!") and Bobby Byrd's ("Yeah!") voices which has been widely sampled in popular music, often in the form of a loop. The drum break was performed by John "Jabo" Starks. It originates from the 1972 Lyn Collins recording "Think (About It)", a song written and produced by Brown, and is just one of a few other frequently used breaks contained in the recording, often collectively known as the Think Break.

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πŸ”— Giffard Dirigible

πŸ”— Aviation πŸ”— Aviation/aircraft

The Giffard dirigible or Giffard airship was an airship built in France in 1852 by Henri Giffard, the first powered and steerable (French: dirigeable – "directable") airship to fly. The craft featured an elongated hydrogen-filled envelope that tapered to a point at each end. From this was suspended a long beam with a triangular, sail-like rudder at its aft end, and beneath the beam a platform for the pilot and steam engine. Due to the highly flammable nature of the lift gas, special precautions were taken to minimise the potential for the envelope to be ignited by the engine beneath it. The engine's exhaust was diverted downwards to a long pipe projecting below the platform, and the area surrounding the boiler's stoke hole was surrounded by wire gauze. On 24 September 1852, Giffard flew the airship from the hippodrome at Place de l'Etoile to Γ‰lancourt, covering the 27Β km (17Β mi) in around 3 hours, demonstrating maneuvering along the way. The engine, however, was not sufficiently powerful to allow Giffard to fly against the wind to make a return journey.

πŸ”— Type 3 Diabetes (Alzheimer's)

πŸ”— Medicine πŸ”— Medicine/Neurology

Type 3 diabetes is a proposed term to describe the interlinked association between type 1 and type 2 diabetes, and Alzheimer's disease. This term is used to look into potential triggers of Alzheimer's disease in people with diabetes.

The proposed progression from diabetes to Alzheimer's disease is inadequately understood; however there are a number of hypotheses describing potential links between the two diseases. The internal mechanism of Insulin resistance and other metabolic risk factors such as hyperglycaemia, caused by oxidative stress and lipid peroxidation are common processes thought to be contributors to the development of Alzheimer's disease in diabetics.

Diagnosis for this disease is different between patients with type 1 and type 2 diabetes. Type 1 diabetes is usually discovered in children and adolescence while type 2 diabetic patients are often diagnosed later in life. While Type 3 diabetes is not a diagnosis in itself, a diagnosis of suspected Alzheimer's disease can be established through observational signs and sometimes with neuroimaging techniques such as Magnetic Resonance Imaging (MRI) to observe abnormalities in diabetic patient's brain tissue.

The techniques used to prevent the disease in patients with diabetes are similar to individuals who do not show signs of the disease. The four pillars of Alzheimer's disease prevention is currently used as a guide for individuals of whom are at risk of developing Alzheimer's disease.

Research into the effectiveness of Glucagon-like Peptide 1 and Melatonin administration to manage the progression of Alzheimer's disease in diabetic patients is currently being conducted to decrease the rate at which Alzheimer's disease progresses.

Labelling Alzheimer's disease as Type 3 Diabetes is generally controversial, and this definition is not a known medical diagnosis. While insulin resistance is a risk factor for the development of Alzheimer's disease and some other dementias, causes of Alzheimer's disease are likely to be much more complex than being explained by insulin factors on their own, and indeed several patients with Alzheimer's disease have normal insulin metabolism.

πŸ”— Rules of Play

πŸ”— Video games πŸ”— Computing πŸ”— Books

Rules of Play: Game Design Fundamentals is a book on game design by Katie Salen and Eric Zimmerman, published by MIT Press.

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πŸ”— Fair Cake-Cutting

πŸ”— Mathematics πŸ”— Game theory

Fair cake-cutting is a kind of fair division problem. The problem involves a heterogeneous resource, such as a cake with different toppings, that is assumed to be divisible – it is possible to cut arbitrarily small pieces of it without destroying their value. The resource has to be divided among several partners who have different preferences over different parts of the cake, i.e., some people prefer the chocolate toppings, some prefer the cherries, some just want as large a piece as possible. The division should be unanimously fair – each person should receive a piece believed to be a fair share.

The "cake" is only a metaphor; procedures for fair cake-cutting can be used to divide various kinds of resources, such as land estates, advertisement space or broadcast time.

The prototypical procedure for fair cake-cutting is divide and choose, which is mentioned in the book of Genesis. It solves the fair division problem for two people. The modern study of fair cake-cutting was initiated during World War II, when Hugo Steinhaus asked his students Stefan Banach and BronisΕ‚aw Knaster to find a generalization of divide-and-choose to three or more people. They developed the last diminisher procedure. Today, fair cake-cutting is the subject of intense research in mathematics, computer science, economics and political science.

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πŸ”— Through-the-Earth Mine Communications

πŸ”— 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.

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