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πŸ”— Imperial Airship Scheme

πŸ”— Aviation πŸ”— Aviation/aircraft πŸ”— United Kingdom πŸ”— British Empire πŸ”— Aviation/Defunct Airlines

The British Imperial Airship Scheme was a 1920s project to improve communication between Britain and the distant countries of the British Empire by establishing air routes using airships. This led to the construction of two large and technically advanced airships, the R100 and the R101. The scheme was terminated in 1931 following the crash of R101 in October 1930 while attempting its first flight to India.

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πŸ”— Proportion-Integral-Derivative Controllers

πŸ”— Systems πŸ”— Systems/Control theory

A proportional–integral–derivative (PID) controller, or three-term controller, is a feedback-based control loop mechanism commonly used to manage machines and processes that require continuous control and automatic adjustment. It is typically used in industrial control systems and various other applications where constant control through modulation is necessary without human intervention. The PID controller automatically compares the desired target value (setpoint or SP) with the actual value of the system (process variable or PV). The difference between these two values is called the error value, denoted as e ( t ) {\displaystyle e(t)} .

It then applies corrective actions automatically to bring the PV to the same value as the SP using three methods: The proportional (P) component responds to the current error value by producing an output that is directly proportional to the magnitude of the error. This provides immediate correction based on how far the system is from the desired setpoint. The integral (I) component, in turn, considers the cumulative sum of past errors to address any residual steady-state errors that persist over time, eliminating lingering discrepancies. Lastly, the derivative (D) component predicts future error by assessing the rate of change of the error, which helps to mitigate overshoot and enhance system stability, particularly when the system undergoes rapid changes. The PID output signal can directly control actuators through voltage, current, or other modulation methods, depending on the application. The PID controller reduces the likelihood of human error and improves automation.

A common example is a vehicle’s cruise control system. For instance, when a vehicle encounters a hill, its speed will decrease if the engine power output is kept constant. The PID controller adjusts the engine's power output to restore the vehicle to its desired speed, doing so efficiently with minimal delay and overshoot.

The theoretical foundation of PID controllers dates back to the early 1920s with the development of automatic steering systems for ships. This concept was later adopted for automatic process control in manufacturing, first appearing in pneumatic actuators and evolving into electronic controllers. PID controllers are widely used in numerous applications requiring accurate, stable, and optimized automatic control, such as temperature regulation, motor speed control, and industrial process management.

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πŸ”— Buddhas of Bamiyan

πŸ”— Religion πŸ”— Central Asia πŸ”— Archaeology πŸ”— Visual arts πŸ”— Buddhism πŸ”— World Heritage Sites πŸ”— Religion/Interfaith πŸ”— Public Art πŸ”— Afghanistan πŸ”— Sculpture πŸ”— Hazara

The Buddhas of Bamiyan were two 6th-century monumental statues of Vairocana Buddha and Gautama Buddha carved into the side of a cliff in the Bamyan valley of central Afghanistan, 130 kilometres (81Β mi) northwest of Kabul at an elevation of 2,500 metres (8,200Β ft). Carbon dating of the structural components of the Buddhas has determined that the smaller 38Β m (125Β ft) "Eastern Buddha" was built around 570 AD, and the larger 55Β m (180Β ft) "Western Buddha" was built around 618 AD.

The statues represented a later evolution of the classic blended style of Gandhara art. The statues consisted of the male Salsal ("light shines through the universe") and the (smaller) female Shamama ("Queen Mother"), as they were called by the locals. The main bodies were hewn directly from the sandstone cliffs, but details were modeled in mud mixed with straw, coated with stucco. This coating, practically all of which wore away long ago, was painted to enhance the expressions of the faces, hands, and folds of the robes; the larger one was painted carmine red and the smaller one was painted multiple colors. The lower parts of the statues' arms were constructed from the same mud-straw mix supported on wooden armatures. It is believed that the upper parts of their faces were made from great wooden masks or casts. The rows of holes that can be seen in photographs held wooden pegs that stabilized the outer stucco.

The Buddhas are surrounded by numerous caves and surfaces decorated with paintings. It is thought that the period of florescence was from the 6th to 8th century AD, until the onset of Islamic invasions. These works of art are considered as an artistic synthesis of Buddhist art and Gupta art from India, with influences from the Sasanian Empire and the Byzantine Empire, as well as the country of Tokharistan.

The statues were blown up and destroyed in March 2001 by the Taliban, on orders from leader Mullah Mohammed Omar, after the Taliban government declared that they were idols. International and local opinion strongly condemned the destruction of the Buddhas. Some Taliban sources credited Omar's decision to blow up the Buddha statues to the growing influence of Osama bin Laden.

πŸ”— The Southwest Effect

πŸ”— Aviation πŸ”— Aviation/airline

The effect, often referred to as "the Southwest effect", is the increase in airline travel originating from a community after service to and from that community is inaugurated by Southwest Airlines, or any similar airline that improves service or lowers cost.

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πŸ”— Bribery of Senior Wehrmacht Officers

πŸ”— Germany πŸ”— Military history πŸ”— Crime πŸ”— Politics πŸ”— Guild of Copy Editors πŸ”— Military history/World War II πŸ”— Military history/German military history πŸ”— Politics/Fascism πŸ”— Military history/European military history

From 1933 to the end of the Second World War, high-ranking officers of the Armed Forces of Nazi Germany accepted vast bribes in the form of cash, estates, and tax exemptions in exchange for their loyalty to Nazism. Unlike bribery at lower ranks in the Wehrmacht, which was also widespread, these payments were regularized, technically legal and made with the full knowledge and consent of the leading Nazi figures.

πŸ”— Bell Labs Holmdel Complex

πŸ”— Architecture πŸ”— New Jersey πŸ”— National Register of Historic Places

The Bell Labs Holmdel Complex, in Holmdel Township, Monmouth County, New Jersey, United States, functioned for 44 years as a research and development facility, initially for the Bell System and later Bell Labs. The centerpiece of the campus is an Eero Saarinen–designed structure that served as the home to over 6,000 engineers and researchers. This modernist building, dubbed "The Biggest Mirror Ever" by Architectural Forum due to its mirror box exterior, was the site of a Nobel Prize discovery, the laser cooling work of Steven Chu.

Restructuring of the company's research efforts reduced the use of the Holmdel Complex, and in 2006 the building was put up for sale. The building has undergone renovations into a multi-purpose living and working space, dubbed Bell Works by its redevelopers. Since 2013 it has been operated by Somerset Development, who redeveloped the building into a mixed-use office for high-tech startup companies. The complex was listed on the National Register of Historic Places in 2017. A number of movies, television programs, and commercials have been filmed at Bell Works, including Severance, The Crowded Room, and Law & Order: Organized Crime.

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πŸ”— The Biggest Star

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πŸ”— Wikipedia tests a new UI design

πŸ”— Religion πŸ”— Biology πŸ”— History of Science πŸ”— Science πŸ”— Evolutionary biology πŸ”— Molecular Biology πŸ”— Creationism πŸ”— Tree of Life πŸ”— Molecular Biology/Genetics

Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction. Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources of genetic variation. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or rare within a population. The evolutionary pressures that determine whether a characteristic would be common or rare within a population constantly change, resulting in a change in heritable characteristics arising over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms and molecules.

The theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the mid-19th century and was set out in detail in Darwin's book On the Origin of Species. Evolution by natural selection was first demonstrated by the observation that more offspring are often produced than can possibly survive. This is followed by three observable facts about living organisms: (1) traits vary among individuals with respect to their morphology, physiology and behaviour (phenotypic variation), (2) different traits confer different rates of survival and reproduction (differential fitness) and (3) traits can be passed from generation to generation (heritability of fitness). Thus, in successive generations members of a population are more likely to be replaced by the progenies of parents with favourable characteristics that have enabled them to survive and reproduce in their respective environments. In the early 20th century, other competing ideas of evolution such as mutationism and orthogenesis were refuted as the modern synthesis reconciled Darwinian evolution with classical genetics, which established adaptive evolution as being caused by natural selection acting on Mendelian genetic variation.

All life on Earth shares a last universal common ancestor (LUCA) that lived approximately 3.5–3.8Β billion years ago. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, to fossilised multicellular organisms. Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis) and loss of species (extinction) throughout the evolutionary history of life on Earth. Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct phylogenetic trees.

Evolutionary biologists have continued to study various aspects of evolution by forming and testing hypotheses as well as constructing theories based on evidence from the field or laboratory and on data generated by the methods of mathematical and theoretical biology. Their discoveries have influenced not just the development of biology but numerous other scientific and industrial fields, including agriculture, medicine, and computer science.

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πŸ”— New York, Ukraine

πŸ”— Ukraine πŸ”— Cities

New York or Niu-York is a rural settlement in Toretsk urban hromada, Bakhmut Raion, Donetsk Oblast, eastern Ukraine. It is located 37.9 kilometres (23.5Β mi) north-northeast from the centre of the city of Donetsk. From 1951 to 2021, the settlement was named Novhorodske.

New York is administratively designated to Toretsk urban hromada, one of the hromadas of Ukraine with its center in the city of Toretsk, that is located about 10 kilometres (6.2Β mi) north of New York. Population: 9,735 (2022 estimate).

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πŸ”— Rosemary Kennedy

πŸ”— United States πŸ”— Biography πŸ”— Women's History πŸ”— Wisconsin πŸ”— United States/Massachusetts - Cape Cod and the Islands

Rose Marie "Rosemary" Kennedy (September 13, 1918 – January 7, 2005) was the eldest daughter born to Joseph P. Kennedy Sr. and Rose Fitzgerald Kennedy. She was a sister of President John F. Kennedy and Senators Robert F. and Ted Kennedy.

In her early young adult years, Rosemary Kennedy experienced seizures and violent mood swings. In response to these issues, her father arranged a prefrontal lobotomy for her in 1941 when she was 23 years of age; the procedure left her permanently incapacitated and rendered her unable to speak intelligibly.

Rosemary Kennedy spent most of the rest of her life being cared for at St. Coletta, an institution in Jefferson, Wisconsin. The truth about her situation and whereabouts was kept secret for decades. While she was initially isolated from her siblings and extended family following her lobotomy, Rosemary did go on to visit them during her later life.