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L4
L4 or L-4 may refer to : Transportation * SP&S Class L-4, an 1884 steam locomotives class * USS ''L-4'' (SS-43), a 1915 United States Navy L-class submarine * HMS ''L4'', a 1918 British L class submarine * Lawson L-4, a 1924 American unflown biplane airliner * Piper Cub (U.S. military designation: L-4), an aircraft * Inline-four engine (L4), a type of inline internal combustion four cylinder engine ** Liberty L-4, a World War I four-cylinder, water-cooled, inline, aero-engine * Lynx Aviation (IATA code) * L4 (New York City bus), a temporary bus route in New York City * Parramatta Light Rail, also known as the L4, a light rail service in Parramatta, Sydney, Australia * Chaika L-4, a Russian twin-engined amphibious aircraft * Soviet submarine L-4 Science and technology * L4 microkernel family, a family of operating system kernels *L4, the transport layer in the OSI model of computer communications * L4, the fourth Lagrangian point in an astronomical orbital configuration * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L4 Microkernel Family
L4 is a family of second-generation microkernels, used to implement a variety of types of operating systems (OS), though mostly for Unix-like, ''Portable Operating System Interface'' (POSIX) compliant types. L4, like its predecessor microkernel L3, was created by German computer scientist Jochen Liedtke as a response to the poor performance of earlier microkernel-based OSes. Liedtke felt that a system designed from the start for high performance, rather than other goals, could produce a microkernel of practical use. His original implementation in hand-coded Intel i386-specific assembly language code in 1993 sparked intense interest in the computer industry. Since its introduction, L4 has been developed to be cross-platform and to improve security, isolation, and robustness. There have been various re-implementations of the original binary L4 kernel application binary interface (ABI) and its successors, including ''L4Ka::Pistachio'' (Karlsruhe Institute of Technology), ''L4/MIPS' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SP&S Class L-4
The Spokane, Portland and Seattle Railway (SP&S) class L-4 steam locomotives were originally used by the Astoria and Columbia River Railroad (AC&R). They became SP&S locomotives when the SP&S acquired the A&CR. Background The Astoria & Columbia River Railroad ran from Portland, Oregon, to Astoria, Oregon, along the south bank of the Columbia River. In 1896-97 several locomotives were obtained secondhand for the newly completed line. Among these locomotives were A&CR numbers 6 and 7. These locomotives would become the two members of Class L-4 when the SP&S bought out the A&CR in 1911. Numbering Upon the acquisition of the A&CR by the SP&S both locomotives were renumbered and placed into Class L-4. A&CR number 6 was renumbered SP&S number 53 on February 24, 1911. A&CR number 7 was renumbered SP&S number 54 on February 24, 1911. Disposition SP&S number 53 was sold to Warren CC on May 6, 1920. SP&S number 54 was dismantled in May 1924. References Rogers locom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lagrangian Point
In celestial mechanics, the Lagrange points (; also Lagrangian points or libration points) are points of equilibrium for small-mass objects under the influence of two massive orbiting bodies. Mathematically, this involves the solution of the restricted three-body problem in which two bodies are far more massive than the third. Normally, the two massive bodies exert an unbalanced gravitational force at a point, altering the orbit of whatever is at that point. At the Lagrange points, the gravitational forces of the two large bodies and the centrifugal force balance each other. This can make Lagrange points an excellent location for satellites, as few orbit corrections are needed to maintain the desired orbit. Small objects placed in orbit at Lagrange points are in equilibrium in at least two directions relative to the center of mass of the large bodies. For any combination of two orbital bodies there are five Lagrange points, L1 to L5, all in the orbital plane of the two lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Level 4 (other) protection level
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Level 4 or Level Four or Level IV may refer to: Technology * Level 4, a level of automation in a self-driving car (see Autonomous car#Classification) *Level 4, the transport layer in the OSI model of computer communications Gradation *Level 4 Biosafety level * Level 4 trauma center Music * LVL IV album by Future Leaders of the World 2004 *Level 4 (Globe album) Other uses * Level 0 coronavirus restrictions, see COVID-19 pandemic in Scotland#Levels System * STANAG 4569 NATO AEP-55 STANAG 4569 is a NATO Standardization Agreement covering the standards for the "Protection Levels for Occupants of Logistic and Light Armored Vehicles". The standard covers strikes from kinetic energy, artillery and IED blasts. Level ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L04 (other)
L04 may refer to: * Holtville Airport's FAA identifier * ATC code L04 Immunosuppressants, a subgroup of the Anatomical Therapeutic Chemical Classification System See also * L4 (other) {{Letter-NumberCombDisambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO/IEC 8859-4
ISO/IEC 8859-4:1998, ''Information technology — 8-bit single-byte coded graphic character sets — Part 4: Latin alphabet No. 4'', is part of the ISO/IEC 8859 series of ASCII-based standard character encodings, first edition published in 1988. It is informally referred to as Latin-4 or ''North European''. It was designed to cover Estonian, Latvian, Lithuanian, Greenlandic, and Sami. It has been largely superseded by ISO/IEC 8859-10 and Unicode. Microsoft has assigned code page 28594 a.k.a. Windows-28594 to ISO-8859-4 in Windows. IBM has assigned code page 914 (CCSID 914) to ISO 8859-4. ISO-8859-4 is the IANA preferred charset name for this standard when supplemented with the C0 and C1 control codes from ISO/IEC 6429 ISO/IEC JTC 1, entitled "Information technology", is a joint technical committee (JTC) of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). Its purpose is to develop, maintain and p .... ISO-IR 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bren Light Machine Gun
The Bren gun was a series of light machine guns (LMG) made by Britain in the 1930s and used in various roles until 1992. While best known for its role as the British and Commonwealth forces' primary infantry LMG in World War II, it was also used in the Korean War and saw service throughout the latter half of the 20th century, including the 1982 Falklands War. Although fitted with a bipod, it could also be mounted on a tripod or be vehicle-mounted. The Bren gun was a licensed version of the Czechoslovak ZGB 33 light machine gun which, in turn, was a modified version of the ZB vz. 26, which British Army officials had tested during a firearms service competition in the 1930s. The later Bren gun featured a distinctive top-mounted curved box magazine, conical flash hider, and quick change barrel. The name ''Bren'' was derived from Brno, the Czechoslovak city in Moravia, where the Zb vz. 26 was designed (in the Zbrojovka Brno Factory) and Enfield, site of the British Royal Small A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caenorhabditis Elegans
''Caenorhabditis elegans'' () is a free-living transparent nematode about 1 mm in length that lives in temperate soil environments. It is the type species of its genus. The name is a blend of the Greek ''caeno-'' (recent), ''rhabditis'' (rod-like) and Latin ''elegans'' (elegant). In 1900, Maupas initially named it '' Rhabditides elegans.'' Osche placed it in the subgenus ''Caenorhabditis'' in 1952, and in 1955, Dougherty raised ''Caenorhabditis'' to the status of genus. ''C. elegans'' is an unsegmented pseudocoelomate and lacks respiratory or circulatory systems. Most of these nematodes are hermaphrodites and a few are males. Males have specialised tails for mating that include spicules. In 1963, Sydney Brenner proposed research into ''C. elegans,'' primarily in the area of neuronal development. In 1974, he began research into the molecular and developmental biology of ''C. elegans'', which has since been extensively used as a model organism. It was the first multicellu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumbar Vertebrae
The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis. They are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse process (since it is only found in the cervical region) and by the absence of facets on the sides of the body (as found only in the thoracic region). They are designated L1 to L5, starting at the top. The lumbar vertebrae help support the weight of the body, and permit movement. Human anatomy General characteristics The adjacent figure depicts the general characteristics of the first through fourth lumbar vertebrae. The fifth vertebra contains certain peculiarities, which are detailed below. As with other vertebrae, each lumbar vertebra consists of a ''vertebral body'' and a ''vertebral arch''. The vertebral arch, consisting of a pair of ''pedicles'' and a pair of ''laminae'', encloses the ''vertebral foramen'' (opening) and sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosomal Protein L4
60S ribosomal protein L4 is a protein that in humans is encoded by the ''RPL4'' gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L4E family of ribosomal proteins. It is located in the cytoplasm. As is typical for genes encoding ribosomal proteins, there are multiple processed pseudogene Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Most arise as superfluous copies of functional genes, either directly by DNA duplication or indirectly by Reverse transcriptase, reverse transcription of an mRNA trans ...s of this gene dispersed through the genome. References Further reading * * * * * * * * * * * * * * * * Ribosomal proteins {{gene-15-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup L4 (mtDNA)
Haplogroup L4 is a human mitochondrial DNA (mtDNA) haplogroup. It is a small maternal clade primarily restricted to Africa. L4 is important in East Africa. The highest frequencies are in Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands and ... among the Hadza at 60-83% and Sandawe at 48%. It has two branches, L4a and L4b. Subgroup L4a was formerly called L7 and considered a separate subclade of L3'4'7. It has been recognized as a subclade of L4, with L3 as its outgroup by Behar et al. (2008). The parent clade L3'4 is to have emerged at 106–66 kya. L4 is not much later than this, estimated at 87 kya by Fernandes et al. (2015).Fernandes V, Triska P, Pereira JB, Alshamali F, Rito T, Machado A, et al. (2015) Genetic Stratigraphy of Key Demographic Events in Arabia. P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-carrier
The L-carrier system was one of a series of carrier systems developed by AT&T for high-capacity transmission for long-distance communications. Over a period from the late 1930s to the 1970s, the system evolved in six significant phases of development, designated by Bell System engineers as L-1 through L-5, and L-5E. Coaxial cable was the principal transmission medium in all stages, initially lending the system another description i.e. the ''coaxial system''.E.L. Green, ''The Coaxial Cable System'', Bell Laboratories Record 15(9) p274 (May 1937) It was the successor to a series of previous carrier systems, typically identified by capital letters. In the 1960s the system was hardened against the dangers of the Cold War using complete placement of all terminal and repeater equipment in hardened underground vaults. Initial development and testing of the coaxial system took place between 1935 and 1937 on a test bed of a 95-mile two-way coaxial cable between locations in New York Cit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
