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Science And Technology In Korea
Like most other regions in the world, science and technology in Korea has experienced periods of intense growth as well as long periods of stagnation. Prehistory At the end of the Palaeolithic, people of the Korean Peninsula adopted microlithic stone tool technology, a highly efficient and useful way of making and maintaining a flexible prehistoric toolkit. The Palaeolithic also marks the beginning of a long period of plant and human interaction in which people undoubtedly adopted a number of wild plants for medicinal use. Archaeological evidence from Gosan-ri in Jeju Island indicates that pottery was first made c. 8500–8000 BC. People depended on gathering, hunting, and fishing as the main source of food until the Middle Jeulmun Period (c. 3500 to 2000 BC) when small-scale cultivation of plants began.Crawford and Lee The earliest known constellation patterns in Korea can be found on dolmens dating back to 3000 BC. Farmers of the Mumun Period began to use multiple cro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeolithic
The Paleolithic or Palaeolithic ( years ago) ( ), also called the Old Stone Age (), is a period in human prehistory that is distinguished by the original development of stone tools, and which represents almost the entire period of human prehistoric technology. It extends from the earliest known use of stone tools by Hominini, hominins, 3.3 million years ago, to the end of the Pleistocene, 11,650 Before Present#Radiocarbon calibration, cal Before Present, BP. The Paleolithic Age in Europe preceded the Mesolithic Age, although the date of the transition varies geographically by several thousand years. During the Paleolithic Age, hominins grouped together in small societies such as band society, bands and subsisted by gathering plants, fishing, and hunting or scavenging wild animals. The Paleolithic Age is characterized by the use of Knapping, knapped stone tools, although at the time humans also used wood and bone tools. Other organic commodities were adapted for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brazier
A brazier () is a container used to burn charcoal or other solid fuel for cooking, heating or rituals. It often takes the form of a metal box or bowl with feet, but in some places it is made of terracotta. Its elevation helps circulate air, feeding oxygen to the fire. Braziers have been used since ancient times; the Nimrud brazier dates to at least 824 BC. History The word brazier is mentioned in the Bible. The Hebrew word for brazier is believed to be of Egyptian origin, suggesting that it was imported from Egypt. The lone reference to it in the Bible being the following verse: The king was sitting in the winter-house in the ninth month; and the brazier () was burning before him. Roman Emperor Jovian was poisoned by the fumes from a brazier in his tent in 364, ending the line of Constantine. In Arabic, the brazier is called ''kanoun''. Uses Heating Despite risks in burning charcoal on open fires, braziers were widely adopted for domestic heating, particularly and somewh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass Transition
The glass–liquid transition, or glass transition, is the gradual and Reversible reaction, reversible transition in amorphous solid, amorphous materials (or in amorphous regions within Crystallinity, semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. International Organization for Standardization, ISO 11357-2: Plastics – Differential scanning calorimetry – Part 2: Determination of glass transition temperature (1999). An amorphous solid that exhibits a glass transition is called a glass. The reverse transition, achieved by supercooling a viscous liquid into the glass state, is called vitrification. The glass-transition temperature ''T''g of a material characterizes the range of temperatures over which this glass transition occurs (as an experimental definition, typically marked as 100 s of relaxation time). It is always lower than the melting point, melting temperature, ''T''m, of the cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stoneware
Stoneware is a broad class of pottery fired at a relatively high temperature, to be impervious to water. A modern definition is a Vitrification#Ceramics, vitreous or semi-vitreous ceramic made primarily from stoneware clay or non-refractory fire clay.Arthur Dodd & David Murfin. ''Dictionary of Ceramics''; 3rd edition. The Institute of Minerals, 1994. This definition excludes stone vessels that are carving, carved from a solid chunk of rock (geology), stone. End applications of stoneware include tableware and ceramic art, decorative ware such as vases. Stoneware is fired at between about to . Historically, reaching such temperatures was a long-lasting challenge, and temperatures somewhat below these were used for a long time. It was developed independently in different locations around the world, after earthenware and before porcelain. Stoneware is not recognised as a category in traditional East Asian terminology, and much Asian stoneware, such as Chinese Ding ware for exampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YouTube
YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in San Bruno, California, it is the second-most-visited website in the world, after Google Search. In January 2024, YouTube had more than 2.7billion monthly active users, who collectively watched more than one billion hours of videos every day. , videos were being uploaded to the platform at a rate of more than 500 hours of content per minute, and , there were approximately 14.8billion videos in total. On November 13, 2006, YouTube was purchased by Google for $1.65 billion (equivalent to $ billion in ). Google expanded YouTube's business model of generating revenue from advertisements alone, to offering paid content such as movies and exclusive content produced by and for YouTube. It also offers YouTube Premium, a paid subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the northernmost, westernmost, and easternmost (the Aleutian Islands cross the 180th meridian into the eastern hemisphere) state in the United States. It borders the Canadian territory of Yukon and the province of British Columbia to the east. It shares a western maritime border, in the Bering Strait, with Russia's Chukotka Autonomous Okrug. The Chukchi and Beaufort Seas of the Arctic Ocean lie to the north, and the Pacific Ocean lies to the south. Technically, it is a semi-exclave of the U.S., and is the largest exclave in the world. Alaska is the largest U.S. state by area, comprising more total area than the following three largest states of Texas, California, and Montana combined, and is the seventh-largest subnational division i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Okjeo
Okjeo () was an History of Korea, ancient Korean tribal state which arose in the northern Korea, Korean peninsula from perhaps the 2nd century BCE to the 5th century CE. Dong-okjeo (Eastern Okjeo) occupied roughly the area of the Hamgyong Province, Hamgyŏng provinces of North Korea, and Buk-okjeo (Northern Okjeo) occupied the Tumen River, Duman River region. Dong-okjeo was often simply called Okjeo, while Buk-okjeo was also sometimes referred to as Chiguru (置溝婁, 치구루) or Guru (구루), the latter name being also applied to Goguryeo. Okjeo bordered the other minor state of Eastern Ye, Dongye on the south, and shared a similar fate. History In its early history, Okjeo oscillated between domination by the Chinese commanderies and by Goguryeo. From the 3rd century BCE to 108 BCE, it was controlled by Gojoseon. At 107 BCE, it became part of the Xuantu Commandery. As the Xuantu Commandery retreated towards the liadong peninsula as a result of expansion of Goguryeo, Ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Chosun Ilbo
''The Chosun Ilbo'' (, ), also known as ''The Chosun Daily,'' is a Korean-language newspaper of record for South Korea and among the oldest active newspapers in the country. With a daily circulation of more than 1,800,000, ''The'' ''Chosun Ilbo'' has been audited annually since the Audit Bureau of Circulations was established in 1993. ''The'' ''Chosun Ilbo'' and its subsidiary company, Digital Chosun, operate the ''Chosun.com'' news website, which also publishes news in English, Chinese, and Japanese. History The Chosun Ilbo Establishment Union was created in September 1919. ''The'' ''Chosun Ilbo'' newspaper was founded on 5 March 1920 by Sin Sogu with the financial support of the Daejong Business Association. Cho Jin-Tae, the vice-chairman of the Daejong Business Association was appointed the first President of the newspaper in 1920. However, as the Business Association failed to pay promised finances, the relationship between the Association and ''The Chosun Ilbo'' broke down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ondol
(; , ; ) or ''gudeul'' (; ) in Korean traditional architecture is underfloor heating that uses direct heat transfer from wood smoke to heat the underside of a thick masonry floor. In modern usage, it refers to any type of underfloor heating, or to a hotel or a sleeping room in Korean (as opposed to Western) style. The main components of the traditional ondol are an '' agungi'' (; ), a '' firebox'' or '' stove'', accessible from an adjoining room (typically kitchen or master bedroom), a raised masonry floor underlain by horizontal smoke passages, and a vertical, freestanding chimney on the opposite exterior wall providing a draft. The heated floor, supported by stone piers or baffles to distribute the smoke, is covered by stone slabs, clay and an impervious layer such as oiled paper. History Origin Use of the has been found at archaeological sites in present-day North Korea. A Neolithic Age archaeological site, ''circa'' 5000 BC, discovered in Sonbong, Rason, in present-day ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Songguk-ri
Songguk-ri () is a Middle and Late Mumun-period (c. 850–300 B.C.) archaeological site in Buyeo-gun, Chungcheongnam-do, South Korea. Songguk-ri is a settlement and burial site that is important in the study of Korean prehistory. It is registered as Historical Site No. 249. Songguk-ri is a main point of reference in Korean prehistory—Korean archaeologists have represented the prehistoric village and the material culture excavated from there as the type-site for Middle Mumun Culture in southern Korea. History of Excavations Excavations began there in 1975 and Songguk-ri was one of the first archaeological sites in South Korea to yield bronze artifacts, large tubular greenstone beads, and pit-houses with rounded plan-shapes. Rounded pit-houses similar with those of Songguk-ri were later found at other archaeological sites along with a suite of other co-occurring artifacts prompting archaeologists to use Songguk-ri as the type site for Middle Mumun culture and label featur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molding (process)
Molding (American English) or moulding ( British and Commonwealth English; see spelling differences) is the process of manufacturing by shaping liquid or pliable raw material using a rigid frame called a mold or matrix. This itself may have been made using a pattern or model of the final object. A mold or mould is a hollowed-out block that is filled with a liquid or pliable material such as plastic, glass, metal, or ceramic raw material. The liquid hardens or sets inside the mold, adopting its shape. A mold is a counterpart to a cast. The very common bi-valve molding process uses two molds, one for each half of the object. Articulated molds have multiple pieces that come together to form the complete mold, and then disassemble to release the finished casting; they are expensive, but necessary when the casting shape has complex overhangs. Piece-molding uses a number of different molds, each creating a section of a complicated object. This is generally only used for larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
