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#2576 2025-08-27 19:19:38

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 51,538

Re: Miscellany

2376) Shinkansen

Gist

The Shinkansen, or "Bullet Train," is Japan's high-speed railway network, known for its speed, reliability, and advanced technology. Opened in 1964 to connect distant regions and facilitate economic growth, the Shinkansen network allows passengers to travel efficiently between major cities like Tokyo, Osaka, and Fukuoka. The trains are characterized by their aerodynamic, bullet-shaped noses and operate on dedicated tracks, with a central management system ensuring high levels of safety.

The Shinkansen, or "Bullet Train," is Japan's high-speed railway network, known for its speed, reliability, and advanced technology. Opened in 1964 to connect distant regions and facilitate economic growth, the Shinkansen network allows passengers to travel efficiently between major cities like Tokyo, Osaka, and Fukuoka. The trains are characterized by their aerodynamic, bullet-shaped noses and operate on dedicated tracks, with a central management system ensuring high levels of safety.

Summary

The Shinkansen, colloquially known in English as the bullet train, is a network of high-speed railway lines in Japan. It was initially built to connect distant Japanese regions with Tokyo, the capital, to aid economic growth and development. Beyond long-distance travel, some sections around the largest metropolitan areas are used as a commuter rail network. It is owned by the Japan Railway Construction, Transport and Technology Agency and operated by five Japan Railways Group companies.

Starting with the Tokaido Shinkansen (515.4 km; 320.3 mi) in 1964, the network has expanded to consist of 2,951.3 km (1,833.9 mi) of lines with maximum speeds of 260–320 km/h (160–200 mph), 283.5 km (176.2 mi) of Mini-shinkansen lines with a maximum speed of 130 km/h (80 mph), and 10.3 km (6.4 mi) of spur lines with Shinkansen services. The network links most major cities on the islands of Honshu and Kyushu, and connects to Hakodate on the northern island of Hokkaido. An extension to Sapporo is under construction and was initially scheduled to open by fiscal year 2030, but in December 2024, it was delayed until the end of FY2038. The maximum operating speed is 320 km/h (200 mph) (on a 387.5 km (241 mi) section of the Tōhoku Shinkansen). Test runs have reached 443 km/h (275 mph) for conventional rail in 1996, and up to a world record 603 km/h (375 mph) for SCMaglev trains in April 2015.

The original Tokaido Shinkansen, connecting Tokyo, Nagoya, and Osaka —three of Japan's largest cities — is one of the world's busiest high-speed rail lines. In the one-year period preceding March 2017, it carried 159 million passengers, and since its opening more than six decades ago, it has transported more than 6.4 billion total passengers. At peak times, the line carries up to 16 trains per hour in each direction with 16 cars each (1,323-seat capacity and occasionally additional standing passengers) with a minimum headway of three minutes between trains.

The Shinkansen network of Japan had the highest annual passenger ridership (a maximum of 353 million in 2007) of any high-speed rail network until 2011, when the Chinese high-speed railway network surpassed it at 370 million passengers annually.

Details

Shinkansen, pioneer high-speed passenger rail system of Japan, with lines on the islands of Honshu, Kyushu, and Hokkaido. It was originally built and operated by the government-owned Japanese National Railways and has been part of the private Japan Railways Group since 1987.

The first section of the original line, a 320-mile (515-km) stretch between Tokyo and Ōsaka, was opened in 1964. Known as the New Tōkaidō Line, it generally follows and is named for the historic and celebrated Tōkaidō (“Eastern Sea Road”) highway that was used especially during the Edo (Tokugawa) period (1603–1867). Inauguration of the line, just before the start of the Tokyo 1964 Olympic Games, was greeted by widespread international acclaim, and the Shinkansen was quickly dubbed the “bullet train” for the great speed the trains obtained and for the aerodynamic bullet shape of their noses. Many innovations, such as the use of prestressed concrete ties and mile-long welded sections of track, were introduced in the line’s construction. A 100-mile (160-km) extension of that line westward from Ōsaka to Okayama was completed in 1972, and its final segment, a 244-mile (393-km) stretch between Okayama and the Hakata station in Fukuoka, northern Kyushu, opened in 1975.

Other lines radiating northward from Tokyo were completed in 1982 to the cities of Niigata (the Jōetsu line) and Morioka (the Tōhoku line), the Tōhoku line subsequently being extended northward to Hachinohe in 2002. Work to build a link to Aomori, northwest of Hachinohe, began in the late 1990s. When that segment opened in 2010, the Shinkansen was essentially complete for the entire length of Honshu. However, plans had long been in place to connect all three main Japanese islands by Shinkansen with a line northward into Hokkaido (via the Seikan Tunnel under Tsugaru Strait). Construction on the Hokkaido line began in 2005 on the segment between Aomori and Hakodate in southern Hokkaido, the ultimate goal being to extend the line to Sapporo. The line between Aomori and Hakodate opened in 2016. Construction on the section from Hakodate to Sapporo was begun in 2012 and expected to be completed in 2031.

Branches from the Tōhoku line to Yamagata opened in 1992 (extended north to Shinjo in 1999) and to Akita in 1997; a branch from the Jōetsu line to Nagano also opened in 1997. Segments of a further extension of the Nagano branch westward to Toyama and Kanazawa opened in 2015. In addition, a line was completed between Yatsushiro and Kagoshima in southwestern Kyushu in 2004. In the late 1990s work commenced to extend that line northward from Yatsushiro to Hakata, and the opening of the segment in 2011 completed the full north-south route of the Shinkansen on Kyushu. Work began in 2008 on a branch from the Kyushu line southwestward to Nagasaki, and it opened in 2022.

Much of the system’s track runs through tunnels, including one under Shimonoseki Strait between Honshu and Kyushu, another on the Tokyo-Niigata line that is 14 miles (23 km) long, and another near Aomori with a record length (for a double-tracked inland tunnel) of 16.5 miles (26.5 km) when the bore was finished in 2005. Several hundred trains operate daily on the Shinkansen system. The most-frequent service is between Tokyo and Ōsaka, especially during the morning and evening rush hours, when trains depart at intervals of 10 minutes or less. The fastest trains can make the trip from Tokyo to Hakata in about five hours, and the quickest from Tokyo to Aomori take about three hours.

The electric multiple-unit trains, which can seat 1,000 passengers or more, derive their power from an overhead wire system. Trains originally reached top speeds of 130 miles (210 km) per hour, but improvements in track, train cars, and other components have made possible maximum speeds of between 150 and 185 miles (240 and 300 km) per hour. In early 2013 some trains began operating at up to 200 miles (320 km) per hour. Such high speeds made it necessary to develop elaborate safety features. Each car, for example, is equipped with brakes consisting of cast-iron discs and metallic pad linings specially designed not to distort under emergency braking. Moreover, all movements of the trains are monitored and controlled by a central computerized facility in Tokyo.

Additional Information


Japan's main islands of Honshu, Kyushu and Hokkaido are served by a network of high speed train lines that connect Tokyo with most of the country's major cities. Japan's high speed trains (bullet trains) are called shinkansen and are operated by Japan Railways (JR).

Running at speeds of up to 320 km/h, the shinkansen is known for punctuality (most trains depart on time to the second), comfort (relatively silent cars with spacious, always forward-facing seats), safety (no fatal accidents in its history) and efficiency. Thanks to various rail passes, the shinkansen can also be a cost-effective means of travel.

Shinkansen network

The shinkansen network consists of multiple lines, among which the Tokaido Shinkansen (Tokyo - Nagoya - Kyoto - Osaka) is the oldest and most popular. All shinkansen lines (except the Akita and Yamagata Shinkansen) run on tracks that are exclusively built for and used by shinkansen trains. Most lines are served by multiple train categories, ranging from the fastest category that stops only at major stations to the slowest category that stops at every station.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#2577 Yesterday 17:59:13

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 51,538

Re: Miscellany

2377) Chimpanzee

Gist

Chimpanzees are highly intelligent primates, demonstrating problem-solving skills, tool use, complex communication, and social intelligence. They can learn to use symbols, understand basic commands, and even display empathy and cultural behaviors. While their brains are smaller than humans, they exhibit remarkable cognitive abilities within their own context.

While chimpanzees can form affectionate bonds and exhibit friendly behavior, their unpredictability means that they can also be dangerous. Their wild instincts, intelligence, and emotional depth make them fascinating, but they also deserve respect. Chimpanzee are not pets and should not be treated as such.

Summary

The chimpanzee, also simply known as the chimp, is a species of great ape native to the forests and savannahs of tropical Africa. It has four confirmed subspecies and a fifth proposed one. When its close relative the bonobo was more commonly known as the pygmy chimpanzee, this species was often called the common chimpanzee or the robust chimpanzee. The chimpanzee and the bonobo are the only species in the genus Pan. Evidence from fossils and DNA sequencing shows that Pan is a sister taxon to the human lineage and is thus humans' closest living relative.

The chimpanzee is covered in coarse black hair but has a bare face, fingers, toes, palms of the hands, and soles of the feet. It is larger and more robust than the bonobo, weighing 40–70 kg (88–154 lb) for males and 27–50 kg (60–110 lb) for females and standing 150 cm (4 ft 11 in).

The chimpanzee lives in groups that range in size from 15 to 150 members, although individuals travel and forage in much smaller groups during the day. The species lives in a strict male-dominated hierarchy, where disputes are generally settled without the need for violence. Nearly all chimpanzee populations have been recorded using tools, modifying sticks, rocks, grass and leaves and using them for hunting and acquiring honey, termites, ants, nuts and water. The species has also been found creating sharpened sticks to spear small mammals. Its gestation period is eight months. The infant is weaned at about three years old but usually maintains a close relationship with its mother for several years more.

The chimpanzee is listed on the IUCN Red List as an endangered species. Between 170,000 and 300,000 individuals are estimated across its range. The biggest threats to the chimpanzee are habitat loss, poaching, and disease. Chimpanzees appear in Western popular culture as stereotyped clown-figures and have featured in entertainments such as chimpanzees' tea parties, circus acts and stage shows. Although chimpanzees have been kept as pets, their strength, aggressiveness, and unpredictability makes them dangerous in this role. Some hundreds have been kept in laboratories for research, especially in the United States. Many attempts have been made to teach languages such as American Sign Language to chimpanzees, with limited success.

Details

A chimpanzee, (Pan troglodytes), is a species of ape that, along with the bonobo, is most closely related to humans. Chimpanzees inhabit tropical forests and savannas of equatorial Africa from Senegal in the west to Lake Albert and northwestern Tanzania in the east. Individuals vary considerably in size and appearance, but chimpanzees stand approximately 1–1.7 metres (3–5.5 feet) tall when erect and weigh about 32–60 kg (70–130 pounds). Males tend to be larger and more robust than females. Chimpanzees are covered by a coat of brown or black hair, but their faces are bare except for a short white beard. Skin colour is generally white except for the face, hands, and feet, which are black. The faces of younger animals may be pinkish or whitish. Among older males and females, the forehead often becomes bald and the back becomes gray.

Natural history

Chimpanzees awaken at dawn, and their day is spent both in the trees and on the ground. After a lengthy midday rest, late afternoon is usually the most intensive feeding period. In the trees, where most feeding takes place, chimps use their hands and feet to move about. They also leap and swing by their arms (brachiate) skillfully from branch to branch. Movement over any significant distance usually takes place on the ground. Though able to walk upright, chimpanzees more often move about on all fours, leaning forward on the knuckles of their hands (knuckle walking). At night they usually sleep in the trees in nests they build of branches and leaves. Chimpanzees are unable to swim, but they will wade in water. The chimpanzee diet is primarily vegetarian and consists of more than 300 different items, mostly fruits, berries, leaves, blossoms, and seeds but also bird eggs and chicks, many insects, and occasionally carrion. Chimpanzees also hunt, both alone and in groups, stalking and killing various mammals such as monkeys, duikers, bushbucks, and wild pigs. They also appear to use certain plants medicinally to cure diseases and expel intestinal parasites.

The female chimpanzee bears a single young at any time of year after a gestation period of about eight months. The newborn weighs about 1.8 kg (about 4 pounds), is almost helpless, and clings to the fur of the mother’s belly as she moves. From about 6 months to 2 years, the youngster rides on the mother’s back. Weaning takes place at about 5 years. Males are considered adults at 16 years of age, and females usually begin to reproduce at about 13 years, but often only two offspring survive during her lifetime. The longevity of chimps is about 45 years in the wild and 58 in captivity; however, older individuals have been documented. For example, Cheetah the chimpanzee, an animal actor from the Tarzan movies of the 1930s and ’40s, was reported to have lived approximately 80 years.

Conservation status

Chimpanzees are an endangered species; their population in the wild has been reduced by hunting (primarily for meat), destruction of habitat from logging or farming, and commercial exportation for use in zoos and research laboratories. The International Union for Conservation of Nature (IUCN) noted that, despite having one of the largest geographic ranges of the great apes, chimpanzee populations have fallen significantly since the 1980s. Lions and leopards also prey upon chimpanzees.

Social behaviour

Chimpanzees are lively animals with more extraverted dispositions than either gorillas or orangutans. They are highly social and live in loose and flexible groups known as communities, or unit groups, that are based on associations between adult males within a home range, or territory. Home ranges of forest-dwelling communities can be as small as a few square kilometres, but home ranges covering hundreds of square kilometres are known among savanna communities. A community can number from 20 or fewer to well over 100 members. Each consists of several subgroups of varying size and unstable composition. Social dominance exists, with adult males being dominant over adult females and adolescent males. Within a community, there are twice or three times as many adult females as adult males; the number of adults is about equal to the number of immature individuals. Communities usually divide into subgroups called parties, which vary widely in size. The dominance hierarchy among male chimpanzees is very fluid; individuals associate with each other and join and leave different subgroups with complete freedom. The dominant (alpha) male of a group can monopolize ovulating females through possessive behaviour. On the other hand, gang attack by subordinate males can expel an alpha male. Males spend all of their lives in the community they are born in, but occasionally a juvenile male may transfer to another community with his mother. In contrast to males, most females leave their group of birth to join a neighbouring group when they mature at around age 11. Female chimpanzees spend most of their time with their young or with other females. Those with dependent offspring are more likely to range alone or in small parties within narrow “core areas.” Females have been known to form coalitions against a bullying adult male or newly immigrated female.

Relations between different chimp communities tend to be hostile. Intruders on a group’s home range may be attacked, and adult males engage in boundary patrol. On rare occasions, a group may invade a neighbouring territory that is much smaller in size, and fatalities among the smaller group result. Infanticide and cannibalism by adult males, and to a lesser extent by adult females, have been observed. Victimized infants are not only those of neighbouring groups but also those born to newly immigrated females. Between- and within-group competition among individuals of the same gender is the likely cause of such violence. Sometimes a male and female will form a consortship, engaging in exclusive mating relationships by leaving other members of the group and staying in the periphery of the group range. This strategy, however, brings increased risk of attack by neighbouring groups.

Chimpanzees exhibit complex social strategies such as cooperation in combat and the cultivation of coalitions and alliances via ranging together, reciprocal grooming, and the sharing of meat (sometimes in exchange for mating opportunities). An alpha male, for instance, may interfere with his rival in grooming with a third party because such a coalition might jeopardize the alpha’s status. On the other hand, the third party might show strategic opportunism in such a situation, since his assistance to either side could determine which of his superiors prevails. Chimpanzees, therefore, appear to have some concept of “trade.” They console, reconcile, and retaliate during fighting and so share emotions and aspects of psychology similar to those found in humans: self-recognition, curiosity, sympathy, grief, and attribution. Although chimps take care of orphaned infants, they also tease handicapped individuals, conceal information that would bring disadvantage to themselves, and manipulate others for their own advantage by expressing deceptive postures, gestures, and facial expressions.

Intelligence

Chimpanzees are highly intelligent and are able to solve many kinds of problems posed to them by human trainers and experimenters. A number of researchers have taught chimpanzees to use sign language or languages based on the display of tokens or pictorial symbols. The implications of these language studies have been contested, however. Critics charge that apes have not acquired true language in the sense of understanding “words” as abstract symbols that can be combined in meaningful new ways. Other investigators maintain that more recent language training has resulted in the chimpanzees’ acquiring a true recognition of “words” as abstractions that can be applied in novel contexts.

Communication between chimps in the wild takes the form of facial expressions, gestures, and a large array of vocalizations, including screams, hoots, grunts, and roars. Males display excitement by standing erect, stamping or swaying, and letting out a chorus of screams. Chimps use louder calls and gestures for long-distance communication (such as drumming on tree buttresses) and quieter calls and facial expressions for short-distance communication. Similarities to human laughter and smiling might be seen in their “play panting” and grinning, respectively.

Various tools are used in several contexts. Chimpanzees “fish” for termites and ants with probes made of grass stalks, vines, branches, peeled bark, and midribs of leaves. They crack hard nuts open by using stones, roots, and wood as hammers or anvils, and they use “leafy sponges” (a handful of folded leaves or moss) to drink water. Branches and leaves are detached and displayed during courtship. In threat displays, chimps throw rocks and drag and throw branches. Sticks are used to inspect dead pythons or other unfamiliar objects that might be dangerous. Leaves are used hygienically in wiping the mouth or other soiled body parts. Chimpanzees also use different tools in succession as a “tool set.” For example, chimpanzees of the Congo basin first dig into termite mounds with a stout stick and then fish for individual termites with a long, slender wand. Tools are also used in combination as “tool composites.” Chimpanzees in the Guinea region push leafy sponges into hollows of trees containing water and then withdraw the wet sponges by using sticks. Chimps thus differ locally in their repertoire of tool use, with younger animals acquiring tool-using behaviours from their elders. Such cultural differences are also seen in food items consumed and in gestural communication. Chimpanzees indeed possess culture when it is defined as the transmission of information from generation to generation via social learning shared by most members of a single age or gender class in a given group.

Chimpanzees’ intelligence, responsiveness, and exuberance have made them ideal nonhuman subjects for psychological, medical, and biological experiments. Young chimpanzees can become very attached to their human trainers, and their expressions of feeling resemble those of humans more closely than any other animal.

Taxonomy

Genetic analysis suggests that the lineages leading to modern humans and chimpanzees diverged from each other between 6.5 million and 9.3 million years ago and that at least 98 percent of the human and chimpanzee genomes are identical. Chimpanzees are classified taxonomically as a single species, Pan troglodytes. (The so-called pygmy chimpanzee, or bonobo, is a distinct and separate species, P. paniscus, that diverged from chimpanzees about 1.7 million years ago.) Four subspecies of P. troglodytes are recognized: the tschego, or Central African chimpanzee (P. troglodytes troglodytes), also known as the common chimpanzee in continental Europe; the West African, or masked, chimpanzee (P. troglodytes verus), known as the common chimpanzee in Great Britain; the East African, or long-haired, chimpanzee (P. troglodytes schweinfurthii); and the Nigerian-Cameroon chimpanzee (P. troglodytes ellioti, which was formerly classified as P. troglodytes vellerosus).

Additional Information

Like us, chimps are highly social animals, care for their offspring for years and can live to be over 50. In fact, chimpanzees are our closest cousins; we share about 98% of our genes.

In their habitat in the forests of Central Africa, chimpanzees spend most of their days in the treetops. When they do come down to earth, chimps usually travel on all fours, though they can walk on their legs like humans for as far as a mile. They use sticks to fish termites out of mounds and bunches of leaves to sop up drinking water.

050825_jb_chimp-chatter_feat.jpg?resize=1380%2C776&ssl=1


It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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