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Casimir element-Symmetric invariant tensors of simple Lie algebras-A Casimir element of order m corresponds to a symmetric invariant tensor of the same order via C(m)=κi1i2⋯imXi1Xi2⋯Xim . Constructing and relating Casimir elements is equivalent to doing the same for symmetric invariant tensors.
Construction of symmet... | milkshake721/2.1M-wiki-STEM |
Casimir element-Symmetric invariant tensors of simple Lie algebras-It is also possible to construct symmetric invariant tensors from the antisymmetric invariant tensors of the type Ωi1i2⋯i2m−1(2m−1)=fi1[i2j1⋯fi2m−3i2m−2]jm−1kj1⋯jm−1i2m−1(m) The symmetric invariant tensor ti1i2⋯im(m)=Ωj1j2⋯j2m−2im(2m−1)fi1j1j2⋯fim−1j2m... | milkshake721/2.1M-wiki-STEM |
Casimir element-Examples-Case of sl(2) The Lie algebra sl2C consists of two-by-two complex matrices with zero trace. There are three standard basis elements, e ,f , and h , with e=[0100],f=[0010],h=[100−1].
The commutators are [e,f]=h,[h,f]=−2f,[h,e]=2e. | milkshake721/2.1M-wiki-STEM |
Casimir element-Examples-One can show that the Casimir element is Case of so(3) The Lie algebra so(3) is the Lie algebra of SO(3), the rotation group for three-dimensional Euclidean space. It is simple of rank 1, and so it has a single independent Casimir. The Killing form for the rotation group is just the Kronecker ... | milkshake721/2.1M-wiki-STEM |
Casimir element-Examples-Consider the irreducible representation of so(3) in which the largest eigenvalue of Lz is ℓ , where the possible values of ℓ are {\textstyle 0,\,{\frac {1}{2}},\,1,\,{\frac {3}{2}},\,\ldots } . The invariance of the Casimir operator implies that it is a multiple of the identity operator I... | milkshake721/2.1M-wiki-STEM |
Casimir element-Examples-For a given value of ℓ , the matrix representation is (2ℓ+1) -dimensional. Thus, for example, the three-dimensional representation for so(3) corresponds to ℓ=1 , and is given by the generators Lx=i(00000−1010);Ly=i(001000−100);Lz=i(0−10100000), where the factors of i are needed for agreeme... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-PLATO (computer system)-PLATO (Programmed Logic for Automatic Teaching Operations), also known as Project Plato and Project PLATO, was the first generalized computer-assisted instruction system. Starting in 1960, it ran on the University of Illinois' ILLIAC I computer. By the late 1970s, it supp... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-PLATO (computer system)-PLATO was designed and built by the University of Illinois and functioned for four decades, offering coursework (elementary through university) to UIUC students, local schools, prison inmates, and other universities. Courses were taught in a range of subjects, including L... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-PLATO (computer system)-Rights to market PLATO as a commercial product were licensed by Control Data Corporation (CDC), the manufacturer on whose mainframe computers the PLATO IV system was built. CDC President William Norris planned to make PLATO a force in the computer world, but found that ma... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Innovations-PLATO was either the first or an earlier example of many now-common technologies: Hardware Plasma display (PLATO IV), c. 1964. Donald Bitzer Touchscreen (PLATO IV), c. 1964. Donald Bitzer Gooch Synthetic Woodwind (music device for the terminal), c. 1972 Display Graphics Charset Edito... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Impetus Before the 1944 G.I. Bill that provided free college education to World War II veterans, higher education was limited to a minority of the US population, though only 9% of the population was in the military. The trend towards greater enrollment was notable by the early 1950s, and... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-The USSR's 1957 launching of the Sputnik I artificial satellite energized the United States' government into spending more on science and engineering education. In 1958, the U.S. Air Force's Office of Scientific Research had a conference about the topic of computer instruction at the Uni... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Genesis Around 1959, Chalmers W. Sherwin, a physicist at the University of Illinois, suggested a computerised learning system to William Everett, the engineering college dean, who, in turn, recommended that Daniel Alpert, another physicist, convene a meeting about the matter with enginee... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Project PLATO was established soon afterwards, and in 1960, the first system, PLATO I, operated on the local ILLIAC I computer. It included a television set for display and a special keyboard for navigating the system's function menus; PLATO II, in 1961, featured two users at once, one o... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-PLATO I, II, and III were funded by small grants from a combined Army-Navy-Air Force funding pool. By the time PLATO III was in operation, everyone involved was convinced it was worthwhile to scale up the project. Accordingly, in 1967, the National Science Foundation granted the team ste... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Multimedia experiences (PLATO IV) In 1972, with the introduction of PLATO IV, Bitzer declared general success, claiming that the goal of generalized computer instruction was now available to all. However, the terminals were very expensive (about $12,000). The PLATO IV terminal had severa... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Touch panel: A 16×16 grid infrared touch panel, allowing students to answer questions by touching anywhere on the screen.
Microfiche images: Compressed air powered a piston-driven microfiche image selector that permitted colored images to be projected on the back of the screen under prog... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-A hard drive for Audio snippets: The random-access audio device used a magnetic disc with a capacity to hold 17 total minutes of pre-recorded audio. It could retrieve for playback any of 4096 audio clips within 0.4 seconds. By 1980, the device was being commercially produced by Education... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-A Votrax voice synthesizer The Gooch Synthetic Woodwind (named after inventor Sherwin Gooch), a synthesizer that offered four-voice music synthesis to provide sound in PLATO courseware. This was later supplanted on the PLATO V terminal by the Gooch Cybernetic Synthesizer, which had sixte... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Influence on PARC and Apple Early in 1972, researchers from Xerox PARC were given a tour of the PLATO system at the University of Illinois. At this time, they were shown parts of the system, such as the Insert Display/Show Display (ID/SD) application generator for pictures on PLATO (late... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-CDC years As PLATO IV reached production quality, William Norris (CDC) became increasingly interested in it as a potential product. His interest was twofold. From a strict business perspective, he was evolving Control Data into a service-based company instead of a hardware one, and was i... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Norris provided CERL with machines on which to develop their system in the late 1960s. In 1971, he set up a new division within CDC to develop PLATO "courseware", and eventually many of CDC's own initial training and technical manuals ran on it. In 1974, PLATO was running on in-house mac... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-CDC announced the acquisition soon after, claiming that by 1985, 50% of the company's income would be related to PLATO services. Through the 1970s, CDC tirelessly promoted PLATO, both as a commercial tool and one for re-training unemployed workers in new fields. Norris refused to give up... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-In the early 1980s, CDC started heavily advertising the service, apparently due to increasing internal dissent over the now $600 million project, taking out print and even radio ads promoting it as a general tool. The Minneapolis Tribune was unconvinced by their ad copy and started an in... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Of course, a computerized system equal to a human should have been a major achievement, the very concept for which the early pioneers in CBT were aiming. A computer could serve all the students in a school for the cost of maintaining it, and wouldn't go on strike. However, CDC charged $5... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-An attempt to mass-market the PLATO system was introduced in 1980 as Micro-PLATO, which ran the basic TUTOR system on a CDC "Viking-721" terminal and various home computers. Versions were built for the TI-99/4A, Atari 8-bit family, Zenith Z-100 and, later, Radio Shack TRS-80 and IBM Pers... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Norris continued to praise PLATO, announcing that it would be only a few years before it represented a major source of income for CDC as late as 1984. In 1986, Norris stepped down as CEO, and the PLATO service was slowly killed off. He later claimed that Micro-PLATO was one of the reason... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-Bitzer was more forthright about CDC's failure, blaming their corporate culture for the problems. He noted that development of the courseware was averaging $300,000 per delivery hour, many times what the CERL was paying for similar products. This meant that CDC had to charge high prices ... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-History-PLATO V: multimedia Intel 8080 microprocessors were introduced in the new PLATO V terminals. They could download small software modules and execute them locally. It was a way to augment the PLATO courseware with rich animation and other sophisticated capabilities. | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Online community-Although PLATO was designed for computer-based education, perhaps its most enduring legacy is its place in the origins of online community. This was made possible by PLATO's groundbreaking communication and interface capabilities, features whose significance is only lately being... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Online community-In much the same way that the PLATO hardware and development platform inspired advances elsewhere (such as at Xerox PARC and MIT), many popular commercial and Internet games ultimately derived their inspiration from PLATO's early games. As one example, Castle Wolfenstein by PLAT... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Online community-The original Freecell by Alfille (from Baker's concept).
Fortner's Airfight, probably the direct inspiration for (PLATO alum) Bruce Artwick's Microsoft Flight Simulator.
Haefeli and Bridwell's Panther (a vector graphics-based tankwar game, anticipating Atari's Battlezone).
Many ... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Online community-Countless games inspired by the role-playing game Dungeons & Dragons, including the original Rutherford/Whisenhunt and Wood dnd (later ported to the PDP-10/11 by Lawrence, who earlier had visited PLATO). and is believed to be the first dungeon crawl game and was followed by: Mor... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Online community-In September 2006 the Federal Aviation Administration retired its PLATO system, the last system that ran the PLATO software system on a CDC Cyber mainframe, from active duty. Existing PLATO-like systems now include NovaNET and Cyber1.org. | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Online community-By early 1976, the original PLATO IV system had 950 terminals giving access to more than 3500 contact hours of courseware, and additional systems were in operation at CDC and Florida State University. Eventually, over 12,000 contact hours of courseware was developed, much of it ... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Custom character sets-In the early 1970s, some people working in the modern foreign languages group at the University of Illinois began working on a set of Hebrew lessons, originally without good system support for leftward writing. In preparation for a PLATO demo in Tehran, that Bruce Sherwood ... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-A PLATO-compatible music language known as OPAL (Octave-Pitch-Accent-Length) was developed for these synthesizers, as well as a compiler for the language, two music text editors, a filing system for m... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-From 1970 to 1994, the University of Illinois (U of I) School of Music explored the use of the Computer-based Education Research Laboratory (CERL) PLATO computer system to deliver online instruction i... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Between 1974 and 1988, 25 U of I music faculty participated in software curriculum development and more than 40 graduate students wrote software and assisted the faculty in its use. In 1988, the proje... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Significant early efforts Pitch recognition/performance judging In 1969, G. David Peters began researching the feasibility of using PLATO to teach trumpet students to play with increased pitch and rhy... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Rhythm notation and perception By 1970, a random access audio device was available for use with PLATO III.In 1972, Robert W. Placek conducted a study that used computer-assisted instruction for rhythm... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Study participants were interviewed about the experience and found it both valuable and enjoyable. Of particular value was PLATO’s immediate feedback. Though participants noted shortcomings in the qua... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-In 1978, William H. Sanders adapted Froseth’s program for delivery using the PLATO IV system. Sanders transferred the slides to microfiche for rear-projection through the PLATO IV terminal’s plasma di... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Sanders and Froseth subsequently conducted a study to compare traditional classroom delivery of the program to delivery using PLATO. The results showed no significant difference between the delivery m... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Musical instrument identification In 1967, Allvin and Kuhn used a four-channel tape recorder interfaced to a computer to present pre-recorded models to judge sight-singing performances.In 1969, Ned C.... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-In 1981, Nan T. Watanabe researched the feasibility of computer-assisted music instruction using computer-controlled pre-recorded audio. She surveyed audio hardware that could interface with a compute... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Watanabe’s computer-based drill-and-practice program taught elementary music education students to identify musical instruments by sound. Students listened to randomly selected instrument sounds, iden... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-The Illinois Technology-based music project By 1988, with the spread of micro-computers and their peripherals, the University of Illinois School of Music PLATO Project was renamed The Illinois Technol... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Influences and impacts Educators and students used the PLATO System for music instruction at other educational institutions including Indiana University, Florida State University, and the University o... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-The goal of this system was to provide tools for music educators to use in the development of instructional materials, which might possibly include music dictation drills, automatically graded keyboar... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-University of Illinois School of Music PLATO Project (Technology and Research-based Chronology)-Another peripheral was the Votrax speech synthesizer, and a "say" instruction (with "saylang" instruction to choose the language) was added to the Tutor programming language to support text-to-speech ... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other Efforts-One of CDC's greatest commercial successes with PLATO was an online testing system developed for National Association of Securities Dealers (now the Financial Industry Regulatory Authority), a private-sector regulator of the US securities markets. During the 1970s Michael Stein, E.... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other Efforts-A number of smaller testing-related companies also evolved from the PLATO system. One of the few survivors of that group is The Examiner Corporation. Dr. Stanley Trollip (formerly of the University of Illinois Aviation Research Lab) and Gary Brown (formerly of Control Data) develop... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other Efforts-In the early 1970s, James Schuyler developed a system at Northwestern University called HYPERTUTOR as part of Northwestern's MULTI-TUTOR computer assisted instruction system. This ran on several CDC mainframes at various sites.Between 1973 and 1980, a group under the direction of T... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other Efforts-CDC eventually sold the "PLATO" trademark and some courseware marketing segment rights to the newly formed The Roach Organization (TRO) in 1989. In 2000 TRO changed their name to PLATO Learning and continue to sell and service PLATO courseware running on PCs. In late 2012, PLATO Le... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other Efforts-The University of Illinois also continued development of PLATO, eventually setting up a commercial on-line service called NovaNET in partnership with University Communications, Inc. CERL was closed in 1994, with the maintenance of the PLATO code passing to UCI. UCI was later rename... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other Efforts-The Evergreen State College received several grants from CDC to implement computer language interpreters and associated programming instruction. Royalties received from the PLATO computer-aided instruction materials developed at Evergreen support technology grants and an annual lec... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other versions-In South Africa During the period when CDC was marketing PLATO, the system began to be used internationally. South Africa was one of the biggest users of PLATO in the early 1980s. Eskom, the South African electrical power company, had a large CDC mainframe at Megawatt Park in the ... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other versions-This was perhaps the most unusual PLATO installation anywhere. Madadeni had about 1,000 students, all of them who were original inhabitants i.e. native population and 99.5% of Zulu ancestry. The college was one of 10 teacher preparation institutions in kwaZulu, most of them much s... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other versions-For many of the Madadeni students, most of whom came from very rural areas, the PLATO terminal was the first time they encountered any kind of electronic technology. Many of the first-year students had never seen a flush toilet before. There initially was skepticism that these tec... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other versions-PLATO was also used fairly extensively in South Africa for industrial training. Eskom successfully used PLM (PLATO learning management) and simulations to train power plant operators, South African Airways (SAA) used PLATO simulations for cabin attendant training, and there were a... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other versions-The South African subsidiary of CDC invested heavily in the development of an entire secondary school curriculum (SASSC) on PLATO, but unfortunately as the curriculum was nearing the final stages of completion, CDC began to falter in South Africa—partly because of financial proble... | milkshake721/2.1M-wiki-STEM |
PLATO (computer system)-Other versions-Cyber1 In August 2004, a version of PLATO corresponding to the final release from CDC was resurrected online. This version of PLATO runs on a free and open-source software emulation of the original CDC hardware called Desktop Cyber. Within six months, by word of mouth alone, more ... | milkshake721/2.1M-wiki-STEM |
Eptapirone-Eptapirone-Eptapirone (F-11,440) is a very potent and highly selective 5-HT1A receptor full agonist of the azapirone family. Its affinity for the 5-HT1A receptor was reported to be 4.8 nM (Ki) (or 8.33 (pKi)), and its intrinsic activity approximately equal to that of serotonin (i.e., 100%).Eptapirone and rel... | milkshake721/2.1M-wiki-STEM |
Eptapirone-Animal studies-In the Porsolt forced swimming test, eptapirone was found to suppress immobility more robustly than buspirone, ipsapirone, flesinoxan, paroxetine, and imipramine, which was suggestive of strong antidepressant-like effects. In this assay, unlike the other drugs screened, buspirone actually incr... | milkshake721/2.1M-wiki-STEM |
Eptapirone-Human studies-Eptapirone has been assayed in humans in preclinical trials at an oral dose of 1.5 mg. In these studies, eptapirone reduced body temperature, prolonged REM sleep, increased cortisol and growth hormone levels, and produced side effects such as dizziness and drowsiness while being overall well to... | milkshake721/2.1M-wiki-STEM |
Conway triangle notation-Conway triangle notation-In geometry, the Conway triangle notation, named after John Horton Conway, allows trigonometric functions of a triangle to be managed algebraically. Given a reference triangle whose sides are a, b and c and whose corresponding internal angles are A, B, and C then the Co... | milkshake721/2.1M-wiki-STEM |
Conway triangle notation-Conway triangle notation-in particular cot cos A=b2+c2−a22 cot cos B=a2+c2−b22 cot cos C=a2+b2−c22 cot ω=a2+b2+c22 where ω is the Brocard angle. The law of cosines is used: cos A cot π3=S33 S2φ=Sφ2−S22SφSφ2=Sφ+Sφ2+S2 for values of φ where 0<φ<π Sϑ+φ=SϑSφ−S2Sϑ+SφSϑ−φ=SϑSφ+S2Sφ−Sϑ.
Furt... | milkshake721/2.1M-wiki-STEM |
All Sky Automated Survey for SuperNovae-All Sky Automated Survey for SuperNovae-The All Sky Automated Survey for SuperNovae (ASAS-SN) is an automated program to search for new supernovae and other astronomical transients, headed by astronomers from the Ohio State University, including Christopher Kochanek and Krzysztof... | milkshake721/2.1M-wiki-STEM |
Thia-crown ether-Thia-crown ether-In organic chemistry, thia-crown ethers are organosulfur compounds which are the thia analogues of crown ethers (cyclic polyethers). That is, they have a sulfur atom (sulfide linkage, −S−) in place of each oxygen atom (ether linkage, −O−) around the ring. While the parent crown ethers ... | milkshake721/2.1M-wiki-STEM |
Thia-crown ether-Thia-crown ether-1,4,7-Trithiacyclononane (9-ane-S3) is a tridentate ligand and forms complexes with many metal ions, including those considered hard, such as copper(II) and iron(II).Tetradentate 14-ane-S4 and the hexadentate 18-ane-S6 are also known. | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Open microfluidics-Microfluidics refers to the flow of fluid in channels or networks with at least one dimension on the micron scale. In open microfluidics, also referred to as open surface microfluidics or open-space microfluidics, at least one boundary confining the fluid flow of a system is remove... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Types of open microfluidics-Open microfluidics can be categorized into various subsets. Some examples of these subsets include open-channel microfluidics, paper-based, and thread-based microfluidics.
Open-channel microfluidics In open-channel microfluidics, a surface tension-driven capillary flow occ... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Types of open microfluidics-Paper-based microfluidics Paper-based microfluidics utilizes the wicking ability of paper for functional readouts. Paper-based microfluidics is an attractive method because paper is cheap, easily accessible, and has a low environmental impact. Paper is also versatile becau... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Types of open microfluidics-Thread-based microfluidics Thread-based microfluidics, an offshoot from paper-based microfluidics, utilizes the same capillary based wicking capabilities. Common thread materials include nitrocellulose, rayon, nylon, hemp, wool, polyester, and silk. Threads are versatile b... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Capillary filaments in open microfluidics-Open capillary microfluidics are channels that expose fluids to open air by excluding the ceiling and/or floor of the channel. Rather than rely on using pumps or syringes to maintain flow, open capillary microfluidics uses surface tension to facilitate the fl... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Capillary filaments in open microfluidics-Capillary filaments in U-groove Rectangular open-surface U-grooves are the easiest type of open microfluidic channel to fabricate. This design can maintain the same order of magnitude velocity in comparison to V-groove. Channels are made of glass or high clar... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Capillary filaments in open microfluidics-Capillary filaments in V-groove V-groove, unlike U-groove, allows for a variety of velocities depending on the groove angle. V-grooves with sharp groove angle result in the interface curvature at the corners explained by reduced Concus-Finn conditions. In a p... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Advantages-One of the main advantages of open microfluidics is ease of accessibility which enables intervention (i.e., for adding or removing reagents) to the flowing liquid in the system. Open microfluidics also allows simplicity of fabrication thus eliminating the need to bond surfaces. When one of... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Advantages-Materials Solutions Thankfully, while many problems exist with PDMS, many solutions have also been developed. To address the negative hydrophobicity and porosity that PDMS exhibits, researchers have started to use coatings such as BSA (bovine serum albumin) or charged molecules to create a... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Disadvantages-Some drawbacks of open microfluidics include evaporation, contamination, and limited flow rate. Open systems are susceptible to evaporation which can greatly affect readouts when fluid volumes are on the microscale. Additionally, due to the nature of open systems, they are more suscepti... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Disadvantages-Materials Polydimethylsiloxane (PDMS) is an ideal material to fabricate microfluidic devices for cell culture applications due to several advantageous properties such as low processing costs, ease of manufacture, rapid prototyping, ease of surface modification, and cellular non-toxicity... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Applications-Like many microfluidic technologies, open system microfluidics has been applied to nanotechnology, biotechnology, fuel cells, and point of care (POC) testing. For cell-based studies, open-channel microfluidic devices enable access to cells for single cell probing within the channel. Othe... | milkshake721/2.1M-wiki-STEM |
Open microfluidics-Applications-Materials Solutions Applications Applications of these solutions are still in use today, as seen by the following examples. In 2014, Lei et al was testing the impedance of human oral cancer cells in the presence of cisplatin, a known anti-cancer drug, by molding the cells into a 3D scaff... | milkshake721/2.1M-wiki-STEM |
Music criticism-Music criticism-The Oxford Companion to Music defines music criticism as "the intellectual activity of formulating judgments on the value and degree of excellence of individual works of music, or whole groups or genres". In this sense, it is a branch of musical aesthetics. With the concurrent expansion ... | milkshake721/2.1M-wiki-STEM |
Music criticism-Nature of music criticism-The musicologist Winton Dean has suggested that "music is probably the most difficult of the arts to criticise." Unlike the plastic or literary arts, the 'language' of music does not specifically relate to human sensory experience – Dean's words, "the word 'love' is common coin... | milkshake721/2.1M-wiki-STEM |
Music criticism-History-To end of 18th century Critical references to music (often deprecating performers or styles) can be found in early literature, including, for example, in Plato's Laws and in the writings of medieval music theorists. | milkshake721/2.1M-wiki-STEM |
Music criticism-History-According to Richard Taruskin, the active concert life of late 18th-century London meant that "the role and the function of arts criticism as we know it today were the creations of the English public." However, the first magazines specifically devoted to music criticism seem to have developed in... | milkshake721/2.1M-wiki-STEM |
Music criticism-History-A further impetus to the direction of music criticism was given by the changing nature of concert programming with the establishment of the European classical music canon; indeed it is at this period that the word 'classical' is first applied to a received musical tradition. At the same time, th... | milkshake721/2.1M-wiki-STEM |
Music criticism-History-In 1798 the Allgemeine musikalische Zeitung, edited by Friedrich Rochlitz (1769–1842), began publication in Leipzig, and this is often regarded as the precursor of a new genre of criticism aimed at a wider readership than qualified connoisseurs. In subsequent years several regular journals dedic... | milkshake721/2.1M-wiki-STEM |
Music criticism-Sources-Avison, Charles (1752). Essay on Musical Expression. London. Downloadable from IMSLP.
Bujic, Bojan (n.d.) "Criticism of Music" in The Oxford Companion to Music, Oxford Music Online, accessed 1 January 2013.
Charlton, David (2003). "Hoffmann as a Writer on Music", in Hoffmann (2003, 1–22).
Conway... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Exploding-bridgewire detonator-The exploding-bridgewire detonator (EBW, also known as exploding wire detonator) is a type of detonator used to initiate the detonation reaction in explosive materials, similar to a blasting cap because it is fired using an electric current. EBWs use a diffe... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-History-The EBW was invented by Luis Alvarez and Lawrence Johnston for the Fat Man–type bombs of the Manhattan Project, during their work in Los Alamos National Laboratory. The Fat Man Model 1773 EBW detonators used an unusual, high reliability detonator system with two EBW "horns" attach... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-EBWs were developed as a means of detonating multiple explosive charges simultaneously, mainly for use in plutonium-based nuclear weapons in which a plutonium core (called a pit) is compressed very rapidly. This is achieved via conventional explosives placed uniformly around t... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-An EBW has two main parts: a piece of fine wire which contacts the explosive, and a high-voltage high-current low-impedance electricity source; it must reliably and consistently supply a rapid starting pulse. When the wire is connected across this voltage, the resulting high c... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-This accounts for the heavy cables seen in photos of the Trinity "Gadget"; high voltage cable requires good insulation and they had to deliver a large current with little voltage drop, lest the EBW not achieve the phase transition quickly enough. | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-The precise timing of EBWs is achieved by the detonator using direct physical effects of the vaporized bridgewire to initiate detonation in the detonator's booster charge. Given a sufficiently high and well known amount of electric current and voltage, the timing of the bridge... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-Conventional blasting caps use electricity to heat a bridge wire rather than vaporize it, and that heating then causes the primary explosive to detonate. Imprecise contact between the bridgewire and the primary explosive changes how quickly the explosive is heated up, and mino... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-Use in nuclear weapons Since explosives detonate at typically 7–8 kilometers per second, or 7–8 meters per millisecond, a 1 millisecond delay in detonation from one side of a nuclear weapon to the other would be longer than the time the detonation would take to cross the weapo... | milkshake721/2.1M-wiki-STEM |
Exploding-bridgewire detonator-Description-In the US, due to their common use in nuclear weapons, these devices are subject to the nuclear control authorities in every state, according to the Guidelines for the Export of Nuclear Material, Equipment and Technology. EBWs are on the United States Munitions List, and expor... | milkshake721/2.1M-wiki-STEM |
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