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LANL is northern New Mexico's largest institution and the largest employer with approximately 8,762 direct employees, 277 guard force, 505 contractors, 1,613 students, 1,143 unionized craft workers, and 452 post-doctoral researchers. Additionally, there are roughly 120 DOE employees stationed at the laboratory to provi... | Wikipedia - Los Alamos National Laboratory | null | null | null |
Professional scientists and students also come to Los Alamos as visitors to participate in scientific projects. The staff collaborates with universities and industry in both basic and applied research to develop resources for the future. The annual budget is approximately US$2.2 billion. | Wikipedia - Los Alamos National Laboratory | null | null | null |
LAP proteins are expressed in a variety of marine organisms as a method of coping with the osmotic threat high salinity poses to the cell. During bouts of high salinity, LAP begins the catalysis of proteins in order to release amino acids into the cell in an attempt to balance the high ion concentrations in the externa... | Wikipedia - Leucyl aminopeptidase | null | null | null |
LBIST that requires additional circuitry (or read-only memory) increases the cost of the integrated circuit. LBIST that only requires temporary changes to programmable logic or rewritable memory avoids this extra cost, but requires more time to first program in the BIST and then to remove it and program in the final co... | Wikipedia - Logic built-in self-test | null | null | null |
LC Control No.: 67106639 Type of Material: Book (Print, Microform, Electronic, etc.) Personal Name: McCall, Storrs, comp. Main Title: Polish logic, 1920-1939 papers by Ajdukiewicz ; Published/Created: Oxford, Clarendon P., 1967. Description: viii, 406 p. 23 cm. Subjects: Logic, Symbolic and mathematical--Addresses, es... | Wikipedia - Polish Logic | null | null | null |
LCE is most commonly used as a part of green building rating systems or individual parties aiming to assess environmental or sustainability consequences of specific building projects or products. Stakeholders that want to develop more sustainable operations on a life-cycle level or assess their products from a life-cyc... | Wikipedia - Life-cycle engineering | null | null | null |
LCS will cycle through these steps repeatedly for some user defined number of training iterations, or until some user defined termination criteria have been met. For online learning, LCS will obtain a completely new training instance each iteration from the environment. For offline learning, LCS will iterate through a ... | Wikipedia - Learning classifier system | null | null | null |
LDP is not a file system, but it uses linked data to produce the kind of information that can be used to create a modern file system abstraction for interacting with HTTP-accessible resources (colloquially referred to as "Web resources"). In contrast, WebDAV is a "set of extensions to the HTTP protocol which allows use... | Wikipedia - Linked Data Platform | null | null | null |
LE-ACL employs a spread spectrum scheme known as adaptive frequency hopping. At the start of each connection event, frequency hopping occurs, with one of the 37 general purpose Bluetooth LE radio channels being selected from the set of available channels using a channel selection algorithm. Each device in the connectio... | Wikipedia - Asynchronous connection-oriented logical transport | null | null | null |
This is a table of data which indicates which channels are available for use and which are not. Implementations mark channels as used or unused according to how well each channel is performing in terms or errors and evidence of interference. Unused channels are not selected by the channel selection algorithm. In this w... | Wikipedia - Asynchronous connection-oriented logical transport | null | null | null |
LEDA is useful in the field of computational geometry due to its support for exact representations of real numbers via the leda_real datatype. This provides an advantage in accuracy over floating-point arithmetic. For example, calculations involving radicals are considerably more accurate when computed using leda_real.... | Wikipedia - Library of Efficient Data types and Algorithms | null | null | null |
LEDA makes use of certifying algorithms to demonstrate that the results of a function are mathematically correct. In addition to the input and output of a function, LEDA computes a third "witness" value which can be used as an input to checker programs to validate the output of the function. LEDA's checker programs wer... | Wikipedia - Library of Efficient Data types and Algorithms | null | null | null |
If not, a Kuratowski subgraph is returned. These values can then be passed directly to checker functions to confirm their validity. A developer only needs to understand the inner-workings of these checker functions to be confident that the result is correct, which greatly reduces the learning curve compared to gaining ... | Wikipedia - Library of Efficient Data types and Algorithms | null | null | null |
LEDA provides four additional numerical representations alongside those built-in to C++: integer, rational, bigfloat, and real: LEDA's integer type offers an improvement over the built-in int datatype by eliminating the problem of overflow at the cost of unbounded memory usage for increasingly large numbers. It follows... | Wikipedia - Library of Efficient Data types and Algorithms | null | null | null |
LEDs and laser diodes usually emit photons with energy close to and slightly larger than the band gap of the semiconductor material from which they are made. Therefore, as the band gap energy increases, the LED or laser color changes from infrared to red, through the rainbow to violet, then to UV. | Wikipedia - Band gap engineering | null | null | null |
LEDs are made from a variety of inorganic semiconductor materials. The following table shows the available colors with wavelength range, voltage drop, and material: | Wikipedia - Light-emitting diode physics | null | null | null |
LENA (Low Energy Neutrino Astronomy) is a liquid scintillation detector with a mass about 50 kton. Its cylindrical shaped tank with about 100 meters height and 30 meters diameter. The actual scintillation volume is surrounded by nylon barrier and buffer volume. Additionally the buffer volume is surrounded by a pure wat... | Wikipedia - Low Energy Neutrino Astronomy | null | null | null |
The detection mechanism of LENA will be the photomultiplier tubes, which are designed to cover partly the walls between buffer volume and water volume. The scintillation light produced in scintillation volume will be detected with those photomultiplier tubes. LENA's aim is to study low energy neutrinos originated by su... | Wikipedia - Low Energy Neutrino Astronomy | null | null | null |
LET assigns a value (which may be the result of an expression) to a variable. In most dialects of BASIC, LET is optional, and a line with no other identifiable keyword will assume the keyword to be LET. DATA holds a list of values which are assigned sequentially using the READ command. READ reads a value from a DATA st... | Wikipedia - BASIC programming language | null | null | null |
An internal pointer keeps track of the last DATA element that was read and moves it one position forward with each READ. Most dialects allow multiple variables as parameters, reading several values in a single operation. | Wikipedia - BASIC programming language | null | null | null |
RESTORE resets the internal pointer to the first DATA statement, allowing the program to begin READing from the first value. Many dialects allow an optional line number or ordinal value to allow the pointer to be reset to a selected location. DIM Sets up an array. | Wikipedia - BASIC programming language | null | null | null |
LFMM (Ligand Field Molecular Mechanics) - functions for the coordination sphere around transition metals based on the angular overlap model (AOM). Implemented in the Molecular Operating Environment (MOE) as DommiMOE and in Tinker VALBOND - a function for angle bending that is based on valence bond theory and works for ... | Wikipedia - Potential energy of protein | null | null | null |
LGBTQ+ individuals tend to be victims of bullying, harassment, and family rejection. Bullying and harassment in school on the basis of sexual orientation has been linked to negative mental health (increased depression and lower self-esteem) and education-related outcomes (increased school absences and lower performance... | Wikipedia - Psychological impact of discrimination on health | null | null | null |
Some researchers also argue that the higher prevalence of clinical mental disorders in the LGBTQ population can be understood as a consequence of the discrimination experienced in their daily environments and interactions.LGBTQ people of color tend to be targets of both racism and heterosexism, which independently pred... | Wikipedia - Psychological impact of discrimination on health | null | null | null |
LI-900 has a bulk density of 144.2 kg/m3 (9 lb/ft3). It was for this reason that it was called the LI-900. It is made from 99.9% pure silica glass fibres, and is 94% air by volume. An LI-900 tile can be heated to 1,204 °C (1,477 K; 2,199 °F) and then immediately plunged into cold water and suffer no damage.Black and wh... | Wikipedia - LI-900 | null | null | null |
White tiles (known as low temperature reusable surface insulation or LRSI) were used mainly on the upper surface and have higher thermal reflectivity. These are therefore pointed towards the sun in order to minimize solar gain. Black tiles (known as high temperature reusable surface insulation or HRSI) are optimized fo... | Wikipedia - LI-900 | null | null | null |
LINCtape, and its derivative, DECtape were variations on this "round tape". They were essentially a personal storage medium, used tape that was 0.75 inches (19 mm) wide and featured a fixed formatting track which, unlike standard tape, made it feasible to read and rewrite blocks repeatedly in place. LINCtapes and DECta... | Wikipedia - Tape storage | null | null | null |
LIQUi|> (pronounced liquid) is a quantum simulation extension on the F# programming language. It is currently being developed by the Quantum Architectures and Computation Group (QuArC) part of the StationQ efforts at Microsoft Research. LIQUi|> seeks to allow theorists to experiment with quantum algorithm design before... | Wikipedia - Quantum program | null | null | null |
LIRS has been deployed in MySQL since version 5.1, and another reference by link. It is also adopted in Infinispan data grid platform. An approximation of LIRS, CLOCK-Pro, is adopted in NetBSD. LIRS is adopted in Apache Jackrabbit, a Content Repository. | Wikipedia - LIRS caching algorithm | null | null | null |
An in-memory LIRS cache is developed in the Red Hat JBoss Data Virtualization System. LIRS is used in the H2 Database Engine, which is called a Scan Resistant Cache. Furthermore, LIRS is used in Apache Impala, a data processing with Hadoop. | Wikipedia - LIRS caching algorithm | null | null | null |
LIRS is a page replacement algorithm with an improved performance over LRU and many other newer replacement algorithms. This is achieved by using reuse distance as a metric for dynamically ranking accessed pages to make a replacement decision. LIRS effectively address the limits of LRU by using recency to evaluate Inte... | Wikipedia - Cache algorithms | null | null | null |
In the time 2 since A4 is accessed, the recency will become 0 for A4 and 1 for A1 because A4 is the most recently accessed Object and IRR will become 4 and it will go on. At time 10, the LIRS algorithm will have two sets LIR set = {A1, A2} and HIR set = {A3, A4, A5}. Now at time 10 if there is access to A4, miss occurs... | Wikipedia - Cache algorithms | null | null | null |
LIRS organizes metadata of cached pages and some uncached pages and conducts its replacement operations described as below, which are also illustrated with an example in the graph. The cache is divided into a Low Inter-reference Recency (LIR) and a High Inter-reference Recency (HIR) partition. The LIR partition is to s... | Wikipedia - LIRS caching algorithm | null | null | null |
All recently accessed pages are placed in a FIFO queue called the LIRS stack (stack S in the graph), and all resident HIR pages are also placed in another FIFO queue (stack Q in the graph). An accessed page is moved to the top of Stack S and any HIR pages at the stack's bottom are removed. For example, Graph (b) is pro... | Wikipedia - LIRS caching algorithm | null | null | null |
When a HIR page in Stack S is accessed, it turns into a LIR page and accordingly the LIR page currently at Stack S’s bottom turns into a HIR page and moves to the top of Stack Q. For example, Graph (c) is produced after page E is accessed on Graph (a). When there is a miss and a resident page has to be replaced, the re... | Wikipedia - LIRS caching algorithm | null | null | null |
LLL is implemented in Arageli as the function lll_reduction_int fpLLL as a stand-alone implementation FLINT as the function fmpz_lll GAP as the function LLLReducedBasis Macaulay2 as the function LLL in the package LLLBases Magma as the functions LLL and LLLGram (taking a gram matrix) Maple as the function IntegerRelati... | Wikipedia - Lenstra–Lenstra–Lovász lattice basis reduction algorithm | null | null | null |
LLOD is defined in relation to Linked Open Data, and LLOD resources (data) should thus conform to licenses in accordance with the Open Definition. For generating the LLOD cloud diagram (and the LOD diagram), this does, however, not seem to be enforced yet, so that the technical criterion is availability over the web an... | Wikipedia - Linguistic Linked Open Data | null | null | null |
As of January 2020, machine-readable license metadata was available for 86 LLOD resources, of these, 82 adopted open licenses, 4 adopted non-commercial licenses.In a broader sense, the term LLOD technology (infrastructures, tools, vocabularies) can also used to refer to the technology independently from whether actuall... | Wikipedia - Linguistic Linked Open Data | null | null | null |
For disambiguation, the terms "LLOD resources" and "LLOD technology" can be used. For emphasizing application or applicability to non-open resources, also "LLD" (Linguistic Linked Data) has been used. A possible compromise is the acronym "LL(O)D" for the technology. A "Licensed Linguistic Linked Data" cloud that contai... | Wikipedia - Linguistic Linked Open Data | null | null | null |
LLSVPs were discovered in full mantle seismic tomographic models of shear velocity as slow features in the lowermost mantle beneath Africa and the Pacific. The boundaries of these features appear fairly consistent across models when applying objective k-means clustering. The global spherical harmonic degree two structu... | Wikipedia - Large low-shear-velocity provinces | null | null | null |
This stable configuration is responsible for the geometry of plate motions at the surface due as well as mantle convection. Another name for the degree two structure, a roughly 200 kilometers (120 miles) thick layer of the lower mantle directly above the core–mantle boundary, is the D″ ("D double-prime" or "D prime pri... | Wikipedia - Large low-shear-velocity provinces | null | null | null |
The LLSVPs lie around the equator, but mostly on the Southern Hemisphere. Global tomography models inherently result in smooth features; local waveform modeling of body waves, however, has shown that the LLSVPs have sharp boundaries. The sharpness of the boundaries makes it difficult to explain the features by temperat... | Wikipedia - Large low-shear-velocity provinces | null | null | null |
Ultra low velocity zones at smaller scales have been discovered mainly at the edges of these LLSVPs.By using the solid Earth tide, the density of these regions has been determined. The bottom two thirds are 0.5% denser than the bulk of the mantle. However, tidal tomography cannot say exactly how the excess mass is dist... | Wikipedia - Large low-shear-velocity provinces | null | null | null |
LM2 algebras are the Boolean algebras. The canonical Łukasiewicz algebra L n {\displaystyle {\mathcal {L}}_{n}} that Moisil had in mind were over the set L_n = { 0, 1/(n − 1), 2/(n − 1), ..., (n-2)/(n-1), 1 } with negation ¬ x = 1 − x {\displaystyle \neg x=1-x} conjunction x ∧ y = min { x , y } {\displaystyle x\wedge y... | Wikipedia - Łukasiewicz–Moisil algebra | null | null | null |
LMDB employs multiversion concurrency control (MVCC) and allows multiple threads within multiple processes to coordinate simultaneous access to a database. Readers scale linearly by design. While write transactions are globally serialized via a mutex, read-only transactions operate in parallel, including in the presenc... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
LMDB makes novel use of well-known computer science techniques such as copy-on-write semantics and B+ trees to provide atomicity and reliability guarantees as well as performance that can be hard to accept, given the library's relative simplicity and that no other similar key-value store database offers the same guaran... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
Reviews run from brief to in-depth. Database developer Oren Eini wrote a 12-part series of articles on his analysis of LMDB, beginning July 9, 2013. The conclusion was in the lines of "impressive codebase ... dearly needs some love", mainly because of too long methods and code duplication. | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
This review, conducted by a .NET developer with no former experience of C, concluded on August 22, 2013 with "beyond my issues with the code, the implementation is really quite brilliant. The way LMDB manages to pack so much functionality by not doing things is quite impressive... I learned quite a lot from the project... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
LMDB was designed to resist data loss in the face of system and application crashes. Its copy-on-write approach never overwrites currently-in-use data. Avoiding overwrites means the structure on disk/storage is always valid, so application or system crashes can never leave the database in a corrupted state. In its defa... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
Even with all asynchronous modes enabled, it is only an OS catastrophic failure or hardware power-loss event rather than merely an application crash that could potentially result in any data corruption. Two academic papers from the USENIX OSDI Symposium covered failure modes of DB engines (including LMDB) under a sudde... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
The paper from Pillai et al., did not find any failure in LMDB that would occur in the real-world file systems considered; the single failure identified by the study in LMDB only relates to hypothetical file systems. The Mai Zheng et al. paper claims to point out failures in LMDB, but the conclusion depends on whether ... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
The selection of fsync or fdatasync is a compile-time switch that is not the default behavior in current Linux builds of LMDB but is the default on macOS, *BSD, Android, and Windows. Default Linux builds of LMDB are, therefore, the only ones vulnerable to the problem discovered by the zhengmai researchers however, LMDB... | Wikipedia - Lightning Memory-Mapped Database | null | null | null |
LNTX-1 belongs to the three-finger toxin family (3FTx) of snake venom toxins. The “three-finger” name refers to the fact that there are distinct three β-strand loops extending from the central globular core. The core of LNTX-1 is rich in disulphide bonds: it has ten conserved cysteine residues, which form five disulphi... | Wikipedia - LNTX-1 | null | null | null |
LNTX belongs to the neurotoxin family; other members include SNTXs (short chain neurotoxins), WNTXs (weak neurotoxins) and MTXs (muscarinic toxins). The particular 3FTx-subtype LNTX-1 falls within the long-chain subfamily and the type II α-neurotoxin sub-subfamily. | Wikipedia - LNTX-1 | null | null | null |
The toxin targets both muscular and neuronal acetylcholine receptors. This dual action is attributed to its structure of eight conserved amino acid residues, Trp25, Asp27, Phe29, Arg33, Arg36, Phe65, Lys23 and Lys49. However, Lys23 and Lys49 residues are only required for muscular acetylcholine receptor binding. | Wikipedia - LNTX-1 | null | null | null |
LOFAR is a European radio interferometer, that measures radio waves with many individual antennas in different places which it combines to a single signal. One of these international LOFAR stations has been constructed in Bornim by Potsdam and is being operated by the AIP. | Wikipedia - Leibniz Institute for Astrophysics Potsdam | null | null | null |
LOM-CH is a metadata profile developed for the education sector in Switzerland. It is currently available in French and German. This application profile was published in July 2014. | Wikipedia - Learning Object Metadata | null | null | null |
LOM-ES is a metadata profile developed for the education sector in Spain. It is available in Spanish. | Wikipedia - Learning Object Metadata | null | null | null |
LOM-FR is a metadata profile developed for the education sector in France. This application profile was first published in 2006. | Wikipedia - Learning Object Metadata | null | null | null |
LOM-GR, also known as "LOM-GR Photodentro" is the Greek LOM application profile for educational resources, currently being used for resources related to school education. It was published in 2012 and is currently available in Greek and English. It is maintained by CTI DIOPHANTUS as part of the "Photodentro Federated Ar... | Wikipedia - Learning Object Metadata | null | null | null |
LOOK has slightly better average seek times than SCAN. C-LOOK has a slightly lower variance in seek time than LOOK since the worst case seek time is nearly cut in half. | Wikipedia - LOOK algorithm | null | null | null |
LOPES Lokomat AutoAmbulator The Mechanized Gait Trainer General Electric's Hardiman (1971) Berkeley Lower Extremity Exoskeleton Ekso bionics | Wikipedia - Neuromechanics of orthoses | null | null | null |
LORAN Data Channel (LDC) is a project underway between the FAA and United States Coast Guard to send low bit rate data using the LORAN system. Messages to be sent include station identification, absolute time, and position correction messages. In 2001, data similar to Wide Area Augmentation System (WAAS) GPS correction... | Wikipedia - Loran-C | null | null | null |
As of November 2005, test messages using LDC were being broadcast from several U.S. LORAN stations.In recent years, LORAN-C has been used in Europe to send differential GPS and other messages, employing a similar method of transmission known as EUROFIX.A system called SPS (Saudi Positioning System), similar to EUROFIX,... | Wikipedia - Loran-C | null | null | null |
LOTC encompasses lateral regions of the visual cortex such as V5 and extrastriate body area. Though LOTC is typically associated with visual processing, sensorimotor mirroring responses and abstract action representations are reliably found in this region. LOTC includes cortical areas that are sensitive to motion, obje... | Wikipedia - Social cognitive neuroscience | null | null | null |
LOVD Alport gene variant databases (COL4A3, COL4A4, COL4A5) | Wikipedia - Collagen alpha-1(IV) chain | null | null | null |
LPS acts as the prototypical endotoxin because it binds the CD14/TLR4/MD2 receptor complex in many cell types, but especially in monocytes, dendritic cells, macrophages and B cells, which promotes the secretion of pro-inflammatory cytokines, nitric oxide, and eicosanoids. Bruce Beutler was awarded a portion of the 2011... | Wikipedia - O antigen | null | null | null |
Humans are much more sensitive to LPS than other animals (e.g., mice). A dose of 1 µg/kg induces shock in humans, but mice will tolerate a dose up to a thousand times higher. This may relate to differences in the level of circulating natural antibodies between the two species. | Wikipedia - O antigen | null | null | null |
Said et al. showed that LPS causes an IL-10-dependent inhibition of CD4 T-cell expansion and function by up-regulating PD-1 levels on monocytes which leads to IL-10 production by monocytes after binding of PD-1 by PD-L1.Endotoxins are in large part responsible for the dramatic clinical manifestations of infections with... | Wikipedia - O antigen | null | null | null |
In another example, the terminal trisaccharide portion (lactotriaose) of the oligosaccharide from pathogenic Neisseria spp. LOS is also found in lactoneoseries glycosphingolipids from human cells. Most meningococci from groups B and C, as well as gonococci, have been shown to have this trisaccharide as part of their LO... | Wikipedia - O antigen | null | null | null |
The presence of these human cell surface 'mimics' may, in addition to acting as a 'camouflage' from the immune system, play a role in the abolishment of immune tolerance when infecting hosts with certain human leukocyte antigen (HLA) genotypes, such as HLA-B35.LPS can be sensed directly by hematopoietic stem cells (HSC... | Wikipedia - O antigen | null | null | null |
LPT might not find the optimal partition. For example, in the above instance the optimal partition {8,7}, {6,5,4}, where both sums are equal to 15. However, its suboptimality is bounded both in the worst case and in the average case; see Performance guarantees below. The running time of LPT is dominated by the sorting,... | Wikipedia - Longest processing time | null | null | null |
LRC encourages forming new teams in the community. It has provided guidance and resources for starting robotics team. There were four teams in LRC during 2008-2009 season, expanded to 17 teams throughout NJ from Jr. FLL to FTC divisions, with more than 100 students and two dozen parent coaches in the 2011-2012 season. | Wikipedia - Livingston Robotics Club | null | null | null |
LRU algorithm cannot be directly implemented in the critical path of computer systems, such as operating systems, due to its high overhead. An approximation of LRU, called CLOCK is commonly used for the implementation. Similarly, CLOCK-Pro is an approximation of LIRS for a low cost implementation in systems. CLOCK-Pro ... | Wikipedia - Cache replacement policies | null | null | null |
First, CLOCK-Pro has three "clock hands" in contrast to a simple structure of CLOCK where only one "hand" is used. With the three hands, CLOCK-Pro is able to measure the reuse distance of data accesses in an approximate way. Second, all the merits of LIRS are retained, such as quickly evicting one-time accessing and/or... | Wikipedia - Cache replacement policies | null | null | null |
LRU can be prohibitively expensive in caches with higher associativity. Practical hardware usually employs an approximation to achieve similar performance at a much lower hardware cost. | Wikipedia - Cache algorithm | null | null | null |
LRU-K evicts the page whose K-th most recent access is furthest in the past. For example, LRU-1 is simply LRU whereas LRU-2 evicts pages according to the time of their penultimate access. LRU-K improves greatly on LRU with regards to locality in time. The ARC algorithm extends LRU by maintaining a history of recently e... | Wikipedia - Page replacement algorithms | null | null | null |
It is particularly resistant to sequential scans. The 2Q algorithm improves upon the LRU and LRU/2 algorithm. By having two queues, one for hot-path items and the other for slow-path items, items are first placed in the slow-path queue and after a second access of the items placed in the hot-path items. Because referen... | Wikipedia - Page replacement algorithms | null | null | null |
LS SPCA requires that the optimal cardinality and subsets of variables forming each SPC are determined by some optimization criterion. In LS SPCA, a reasonable approach is to choose the lowest cardinality for which an SPC explains a given percentage of the cumulative variance explained by the corresponding standard PC.... | Wikipedia - Sparse PCA | null | null | null |
LS-DYNA's contact algorithms: Flexible body contact Flexible body to rigid body contact Rigid body to rigid body contact Edge-to-edge contact Eroding contact Tied surfaces CAD surfaces Rigid walls Draw beads | Wikipedia - LS-DYNA | null | null | null |
LSCs based on cadmium selenide/zinc sulfide (CdSe/ZnS) and cadmium selenide/cadmium sulfide (CdSe/CdS) quantum dots (QD) with induced large separation between emission and absorption bands (called a large Stokes shift) were announced in 2007 and 2014 respectivelyLight absorption is dominated by an ultra-thick outer she... | Wikipedia - Luminescent solar concentrator | null | null | null |
The active particles were about one hundred angstroms across.Spectroscopic measurements indicated virtually no re-absorption losses on distances of tens of centimeters. Photon harvesting efficiencies were approximately 10%. Despite their high transparency, the fabricated structures showed significant enhancement of sol... | Wikipedia - Luminescent solar concentrator | null | null | null |
LSD is a chiral compound with two stereocenters at the carbon atoms C-5 and C-8, so that theoretically four different optical isomers of LSD could exist. LSD, also called (+)-D-LSD, has the absolute configuration (5R,8R). The C-5 isomers of lysergamides do not exist in nature and are not formed during the synthesis fro... | Wikipedia - Lysergic acid diethylamide | null | null | null |
However, LSD and iso-LSD, the two C-8 isomers, rapidly interconvert in the presence of bases, as the alpha proton is acidic and can be deprotonated and reprotonated. Non-psychoactive iso-LSD which has formed during the synthesis can be separated by chromatography and can be isomerized to LSD. Pure salts of LSD are trib... | Wikipedia - Lysergic acid diethylamide | null | null | null |
LSD is an ergoline derivative. It is commonly synthesized by reacting diethylamine with an activated form of lysergic acid. Activating reagents include phosphoryl chloride and peptide coupling reagents. Lysergic acid is made by alkaline hydrolysis of lysergamides like ergotamine, a substance usually derived from the er... | Wikipedia - Model psychosis | null | null | null |
LSD may be quantified in urine as part of a drug abuse testing program, in plasma or serum to confirm a diagnosis of poisoning in hospitalized victims or in whole blood to assist in a forensic investigation of a traffic or other criminal violation or a case of sudden death. Both the parent drug and its major metabolite... | Wikipedia - Lysergic acid diethylamide | null | null | null |
LSD may trigger panic attacks or feelings of extreme anxiety, known colloquially as a "bad trip". Although population studies have not found an increased incidence of mental illness in psychedelic drug users overall, with psychedelic users actually having lower rates of depression and substance abuse than the control g... | Wikipedia - Model psychosis | null | null | null |
LSECs have been reported to play a role in the development of liver fibrosis. Liver fibrosis is associated with decreased LSEC fenestration, and appearance of an organized basal lamina in the space of Disse, a process called capillarization, which precedes the onset of liver fibrosis. Normally differentiated LSECs prev... | Wikipedia - Liver sinusoidal endothelial cell | null | null | null |
LSECs play a central role in the clearance of blood borne waste. The cells express endocytosis receptors that mediate extremely rapid internalization of waste molecules. In rat it has been shown that LSECs express scavenger receptors (SR) class A, B, E and H. The latter exists as stabilin-1 (SR-H1) and stabilin-2 (SR-H... | Wikipedia - Liver sinusoidal endothelial cell | null | null | null |
Moreover, LSECs also express high levels of the macrophage mannose receptor (MMR) and the Fc-gamma receptor IIb2 (FcγRIIb2), both highly active in clathrin-mediated endocytosis just like the two stabilins. Other important receptors on LSECs are L-SIGN (liver/lymph node-specific ICAM-3 grabbing nonintegrin), LSECtin (li... | Wikipedia - Liver sinusoidal endothelial cell | null | null | null |
LSI begins by constructing a term-document matrix, A {\displaystyle A} , to identify the occurrences of the m {\displaystyle m} unique terms within a collection of n {\displaystyle n} documents. In a term-document matrix, each term is represented by a row, and each document is represented by a column, with each matrix ... | Wikipedia - Latent semantic indexing | null | null | null |
Once a term-document matrix is constructed, local and global weighting functions can be applied to it to condition the data. The weighting functions transform each cell, a i j {\displaystyle a_{ij}} of A {\displaystyle A} , to be the product of a local term weight, l i j {\displaystyle l_{ij}} , which describes the rel... | Wikipedia - Latent semantic indexing | null | null | null |
Some common global weighting functions are defined in the following table. Empirical studies with LSI report that the Log and Entropy weighting functions work well, in practice, with many data sets. In other words, each entry a i j {\displaystyle a_{ij}} of A {\displaystyle A} is computed as: g i = 1 + ∑ j p i j log ... | Wikipedia - Latent semantic indexing | null | null | null |
LSI uses common linear algebra techniques to learn the conceptual correlations in a collection of text. In general, the process involves constructing a weighted term-document matrix, performing a Singular Value Decomposition on the matrix, and using the matrix to identify the concepts contained in the text. | Wikipedia - Latent semantic indexing | null | null | null |
LTI system theory describes linear time-invariant (LTI) filters of all types. LTI filters can be completely described by their frequency response and phase response, the specification of which uniquely defines their impulse response, and vice versa. From a mathematical viewpoint, continuous-time IIR LTI filters may be ... | Wikipedia - Linear filters | null | null | null |
Similarly, discrete-time LTI filters may be analyzed via the Z-transform of their impulse response. Before the advent of computer filter synthesis tools, graphical tools such as Bode plots and Nyquist plots were extensively used as design tools. Even today, they are invaluable tools to understanding filter behavior. | Wikipedia - Linear filters | null | null | null |
Reference books had extensive plots of frequency response, phase response, group delay, and impulse response for various types of filters, of various orders. They also contained tables of values showing how to implement such filters as RLC ladders - very useful when amplifying elements were expensive compared to passiv... | Wikipedia - Linear filters | null | null | null |
Many different analog filter designs have been developed, each trying to optimise some feature of the system response. For practical filters, a custom design is sometimes desirable, that can offer the best tradeoff between different design criteria, which may include component count and cost, as well as filter response... | Wikipedia - Linear filters | null | null | null |
These can be implemented as analog circuits (for instance, using a Sallen Key filter topology, a type of active filter), or as algorithms in digital signal processing systems. Digital filters are much more flexible to synthesize and use than analog filters, where the constraints of the design permits their use. Notably... | Wikipedia - Linear filters | null | null | null |
FIR digital filters may be implemented by the direct convolution of the desired impulse response with the input signal. They can easily be designed to give a matched filter for any arbitrary pulse shape. | Wikipedia - Linear filters | null | null | null |
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