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https://en.wikipedia.org/wiki/Lsh | lsh is a free software implementation of the Secure Shell (SSH) protocol version 2, by the GNU Project including both server and client programs. Featuring Secure Remote Password protocol (SRP) as specified in secsh-srp besides, public-key authentication. Kerberos is somewhat supported as well. Currently however for password verification only, not as a single sign-on (SSO) method.
lsh was started from scratch and predates OpenSSH.
Karim Yaghmour concluded in 2003 that lsh was "not fit for use" in production embedded Linux systems, because of its dependencies upon other software packages that have a multiplicity of further dependencies. The lsh package requires the GNU MP library, zlib, and liboop, the latter of which in turn requires GLib, which then requires pkg-config. Yaghmour further notes that lsh suffers from cross-compilation problems that it inherits from glib. "If […] your target isn't the same architecture as your host," he states, "LSH isn't a practical choice at this time."
Debian provides packages of lsh as lsh-server, lsh-utils, lsh-doc and lsh-client.
See also
Comparison of SSH servers
Comparison of SSH clients
TCP Wrappers
GnuTLS |
https://en.wikipedia.org/wiki/Emojli | Emojli was a social application for iOS and Android, created by YouTuber and web developer Tom Scott, and YouTuber and broadcast engineer Matt Gray. Usernames could contain only emoji and users could only communicate using emoji within the app.
History
Tom Scott and Matt Gray were inspired to create the app after seeing the success of Yo and the release of new emoji characters by the Unicode Consortium. During a talk at Electromagnetic Field Festival, the developers commented that the app originated largely as a joke, but that by the time of launch 70,000 unique usernames had been reserved. The app was launched on 29 August 2014. After press coverage the developers began receiving offers for venture capital.
Due to the cost and effort of maintaining the application, the developers closed the app on 30 July 2015.
Development
The back end of the app was coded by Tom Scott in PHP and MySQL and the front end was designed and programmed by Matt Gray in HTML, CSS and JavaScript.
The pair remarked that they ran into problems as not all web browsers supported emoji, and mobile operating system support for them varied. All work on the app was done in their spare time and took a little over a month.
The iOS version of the app was released on 29 August 2014. The Android version was released on 30 January 2015.
The app shut down on 30 July 2015. |
https://en.wikipedia.org/wiki/Fragment%20molecular%20orbital | The fragment molecular orbital method (FMO) is a computational method that can be used to calculate very large molecular systems with thousands of atoms using ab initio quantum-chemical wave functions.
History of FMO and related methods
The fragment molecular orbital method (FMO) was developed by Kazuo Kitaura and coworkers in 1999. FMO is deeply interconnected with the energy decomposition analysis (EDA) by Kazuo Kitaura and Keiji Morokuma, developed in 1976. The main use of FMO is to compute very large molecular systems by dividing them into fragments and performing ab initio or density functional quantum-mechanical calculations of fragments and their dimers, whereby the Coulomb field from the whole system is included. The latter feature allows fragment calculations without using caps.
The mutually consistent field (MCF) method had introduced the idea of self-consistent fragment calculations in their embedding potential, which was later used with some modifications in various methods including FMO. There had been other methods related to FMO including the incremental correlation method by H. Stoll (1992).
Later, other methods closely related to FMO were proposed including the kernel energy method of L. Huang and the electrostatically embedded many-body expansion by E. Dahlke,
S. Hirata and later M. Kamiya suggested approaches also very closely related to FMO. Effective fragment molecular orbital (EFMO) method combines some features of the effective fragment potentials (EFP) and FMO. A detailed perspective on the fragment-based method development can be found in a review.
Introduction to FMO
In addition to the calculation of the total properties, such as the energy,
energy gradient, dipole moment etc., an interaction energy is obtained for
each pair of fragments. This pair interaction energy can be further
decomposed into electrostatic, exchange, charge transfer and dispersion
contributions. This analysis is known as the pair interaction energy
decompositi |
https://en.wikipedia.org/wiki/Static%20induction%20thyristor | The static induction thyristor (SIT, SITh) is a thyristor with a buried gate structure in which the gate electrodes are placed in n-base region. Since they are normally on-state, gate electrodes must be negatively or anode biased to hold off-state. It has low noise, low distortion, high audio frequency power capability. The turn-on and turn-off times are very short, typically 0.25 microseconds.
History
The first static induction thyristor was invented by Japanese engineer Jun-ichi Nishizawa in 1975. It was capable of conducting large currents with a low forward bias and had a small turn-off time. It had a self controlled gate turn-off thyristor that was commercially available through Tokyo Electric Co. (now Toyo Engineering Corporation) in 1988. The initial device consisted of a p+nn+ diode and a buried p+ grid.
In 1999, an analytical model of the SITh was developed for the PSPICE circuit simulator. In 2010, a newer version of SITh was developed by Zhang Caizhen, Wang Yongshun, Liu Chunjuan and Wang Zaixing, the new feature of which was its high forward blocking voltage.
See also
Static induction transistor
MOS composite static induction thyristor |
https://en.wikipedia.org/wiki/Extended%20Unix%20Code | Extended Unix Code (EUC) is a multibyte character encoding system used primarily for Japanese, Korean, and simplified Chinese.
The most commonly used EUC codes are variable-length encodings with a character belonging to an compliant coded character set (such as ASCII) taking one byte, and a character belonging to a 94x94 coded character set (such as ) represented in two bytes. The EUC-CN form of and EUC-KR are examples of such two-byte EUC codes. EUC-JP includes characters represented by up to three bytes, including an initial , whereas a single character in EUC-TW can take up to four bytes.
Modern applications are more likely to use UTF-8, which supports all of the glyphs of the EUC codes, and more, and is generally more portable with fewer vendor deviations and errors. EUC is however still very popular, especially EUC-KR for South Korea.
Encoding structure
The structure of EUC is based on the standard, which specifies a system of graphical character sets that can be represented with a sequence of the 94 7-bit bytes 0x21–7E, or alternatively 0xA1–FE if an eighth bit is available. This allows for sets of 94 graphical characters, or 8836 (942) characters, or 830584 (943) characters. Although initially 0x20 and 0x7F were always the space and and 0xA0 and 0xFF were unused, later editions of allowed the use of the bytes 0xA0 and 0xFF (or 0x20 and 0x7F) within sets under certain circumstances, allowing the inclusion of 96-character sets. The ranges 0x00–1F and 0x80–9F are used for C0 and C1 control codes.
EUC is a family of 8-bit profiles of , as opposed to 7-bit profiles such as ISO-2022-JP. As such, only compliant character sets can have EUC forms. Up to four coded character sets (referred to as G0, G1, G2, and G3 or as code sets 0, 1, 2, and 3) can be represented with the EUC scheme. The G0 set is set to an compliant coded character set such as US-ASCII, () or (the lower half of ) and invoked over GL (i.e. 0x21–0x7E, with the most significant bit cleared |
https://en.wikipedia.org/wiki/CD4%20immunoadhesin | CD4 immunoadhesin is a recombinant fusion protein consisting of a combination of CD4 and the fragment crystallizable region, similarly known as immunoglobulin. It belongs to the antibody (Ig) gene family. CD4 is a surface receptor for human immunodeficiency virus (HIV). The CD4 immunoadhesin molecular fusion allow the protein to possess key functions from each independent subunit. The CD4 specific properties include the gp120-binding and HIV-blocking capabilities. Properties specific to immunoglobulin are the long plasma half-life and Fc receptor binding. The properties of the protein means that it has potential to be used in AIDS therapy as of 2017. Specifically, CD4 immunoadhesin plays a role in antibody-dependent cell-mediated cytotoxicity (ADCC) towards HIV-infected cells. While natural anti-gp120 antibodies exhibit a response towards uninfected CD4-expressing cells that have a soluble gp120 bound to the CD4 on the cell surface, CD4 immunoadhesin, however, will not exhibit a response. One of the most relevant of these possibilities is its ability to cross the placenta.
History and significance
CD4 immunoadhesin was first developed in the mid-1990s as a potential therapeutic agent and treatment for HIV/AIDS. The protein is a fusion of the extracellular domain of the CD4 receptor and the Fc domain of human immunoglobulin G (IgG), the most abundant antibody isotype in the human body. The Fc domain of IgG contributes several important properties to the fusion protein, including increased half-life in the bloodstream, enhanced binding to Fc receptors on immune cells, and the ability to activate complement.
The development of CD4 immunoadhesin stems from the observation that the CD4 receptor plays a critical role in the entry of HIV into human cells. The CD4 receptor is used as a primary receptor by HIV to attach to the surface of target cells. HIV then uses a co-receptor, either CCR5 or CXCR4, to facilitate entry into the cell. The ability of CD4 immunoadhesin to |
https://en.wikipedia.org/wiki/Pseudomonas%20phage%20F116%20holin | The Pseudomonas phage F116 holin is a non-characterized holin homologous to one in Neisseria gonorrheae that has been characterized. This protein is the prototype of the Pseudomonas phage F116 holin (F116 Holin) family (TC# 1.E.25), which is a member of the Holin Superfamily II. Bioinformatic analysis of the genome sequence of N. gonorrhoeae revealed the presence of nine probable prophage islands. The genomic sequence of FA1090 identified five genomic regions (NgoPhi1 - 5) that are related to dsDNA lysogenic phage. The DNA sequences from NgoPhi1, NgoPhi2 and NgoPhi3 contained regions of identity. A region of NgoPhi2 showed high similarity with the Pseudomonas aeruginosa generalized transducing phage F116. NgoPhi1 and NgoPhi2 encode functionally active phages. The holin gene of NgoPhi1 (identical to that encoded by NgoPhi2), when expressed in E. coli, could substitute for the phage lambda S gene.
See also
Holin
Lysin
Transporter Classification Database |
https://en.wikipedia.org/wiki/Pursuit%20curve | In geometry, a curve of pursuit is a curve constructed by analogy to having a point or points representing pursuers and pursuees; the curve of pursuit is the curve traced by the pursuers.
With the paths of the pursuer and pursuee parameterized in time, the pursuee is always on the pursuer's tangent. That is, given , the pursuer (follower), and , the pursued (leader), for every with there is an such that
History
The pursuit curve was first studied by Pierre Bouguer in 1732. In an article on navigation, Bouguer defined a curve of pursuit to explore the way in which one ship might maneuver while pursuing another.
Leonardo da Vinci has occasionally been credited with first exploring curves of pursuit. However Paul J. Nahin, having traced such accounts as far back as the late 19th century, indicates that these anecdotes are unfounded.
Single pursuer
The path followed by a single pursuer, following a pursuee that moves at constant speed on a line, is a radiodrome.
It is a solution of the differential equation
.
Multiple pursuers
Typical drawings of curves of pursuit have each point acting as both pursuer and pursuee, inside a polygon, and having each pursuer pursue the adjacent point on the polygon. An example of this is the mice problem.
See also
Logarithmic spiral
Tractrix
Circles of Apollonius#Apollonius pursuit problem
Pursuit–evasion |
https://en.wikipedia.org/wiki/C15orf39 | C15orf39 is a protein that in humans is encoded by the Chromosome 15 open reading frame 15 (C15orf39) gene.
Gene
Location
C15orf39 is located on chromosome 15 (15q24.2), spanning 16.53kb from 75487985 to 75504515 on the plus DNA strand. C15orf39 has three exons, and seven introns.
mRNA
Isoforms
The coding sequence for the C15orf39 mRNA is 4443 base pairs long. The C15orf39 gene produces seven mRNA transcripts, with the longest coding isoform being 1047 amino acids long, and the shortest being 27 amino acids which has a truncated 3' end.
Expression
C15orf39 is highly expressed in the trigeminal ganglion, superior cervical ganglion, whole blood, and the heart. Low expression levels of C15orf39 were found in the occipital lobe and PB-CD19+ B-cells.
.
.
C15orf39 expression levels in fetal and adult reticulocytes showed significantly different levels of expression (P < 0.0001), with adult reticulocytes expressing more C15orf39 than fetal cells.
.
.
.
.
Protein
General Properties
C15orf39 has an unmodified molecular mass of 110.6 kDA. The modified molecular mass is 110.7 kDA. C15orf39 is composed of an above average level of proline (≈17%), and is deficient in isoleucine (≈1%) and asparagine (≈1%). Both close (Thirteen-lined ground squirrel) and distant (Crested-Ibis) orthologs contained above average levels of proline, and low levels of isoleucine, and asparagine.
Domains and Motifs
C15orf39 has four predicted domains. Two of which, are the proline rich and alanine rich domains. The large tegument protein UL36 domain is important in the regulation of the viral cycle of Human Herpes Virus 1 (HHV-1), including transporting the viral capsid to the nuclear pore complex, and linking the inner and outer viral tegument capsids together. Lastly, the WH2 domain, WASP-homology domain 2, is approximately 18 amino acids long, and serves as an actin binding domain. WH2 binds actin monomers enabling the production of actin filaments.
Post-Translational Modifications |
https://en.wikipedia.org/wiki/Lightning%20Network | The Lightning Network (LN) is a "layer 2" payment protocol built on the Bitcoin blockchain and those of other cryptocurrencies. It is intended to enable fast transactions among participating nodes (independently run members of the network) and has been proposed as a solution to the bitcoin scalability problem. It is a peer-to-peer system for making micropayments of cryptocurrency through a network of bidirectional payment channels, without delegating custody of funds.
Transacting parties use the Lightning Network by opening a payment channel and transferring (committing) funds to the relevant layer-1 blockchain (e.g. Bitcoin) under a smart contract. The parties then make any number of off-chain Lightning Network transactions that update the tentative distribution of the channel's funds, without broadcasting to the blockchain. Whenever the parties have finished their transaction session, they close the payment channel, and the smart contract distributes the committed funds according to the transaction record.
To initiate closing, one node first broadcasts the current state of the transaction record to the network, including a proposed settlement, a distribution of the committed funds. If both parties confirm the proposal, the funds are immediately paid on-chain. The other option is uncooperative closure, for example if one node has dropped from the network, or if it is broadcasting an incorrect (possibly fraudulent) transaction state. In this case settlement is delayed during a dispute period, when nodes may contest the proposal. If the second node broadcasts a more up-to-date timestamped distribution, including some transactions omitted by the first proposal, then all committed funds are transferred to the second node: this punitive breach remedy transaction thwarts attempts to defraud the other node by broadcasting out-of-date transactions.
History
Joseph Poon and Thaddeus Dryja published a Lightning Network white paper in February 2015.
2019 Bitcoin Lightning |
https://en.wikipedia.org/wiki/TL431 | The TL431 integrated circuit (IC) is a three-terminal adjustable precise shunt voltage regulator. With the use of an external voltage divider, a TL431 can regulate voltages ranging from 2.495 to 36 V, at currents up 100 mA. The typical initial deviation of reference voltage from the nominal 2.495 V level is measured in millivolts, the maximum worst-case deviation is measured in tens of millivolts. The circuit can control power transistors directly; combinations of the TL431 with power MOS transistors are used in high efficiency, very low dropout linear regulators. The TL431 is the de facto industry standard error amplifier circuit for switched-mode power supplies with optoelectronic coupling of the input and output networks.
Texas Instruments introduced the TL431 in 1977. In the 21st century, the original TL431 remains in production along with a multitude of clones and derivatives (TLV431, TL432, ATL431, KA431, LM431, TS431, 142ЕН19 and others). These functionally similar circuits may differ considerably in die size and layout, precision and speed characteristics, minimal operating currents, safe operating areas, and specific voltage reference.
Construction and operation
The TL431 is functionally equivalent to an ideal npn bipolar transistor switch with a stable 2.495 V switching threshold and no apparent hysteresis. "Base", "collector" and "emitter" of this "transistor" are traditionally called reference (R or REF), cathode (C) and anode (A). The positive control voltage, VREF, is applied between reference input and the anode; the output current, ICA, flows from the cathode to the anode.
On a functional level the TL431 contains an open-loop operational amplifier that compares the input control voltage with a 2.495 V voltage reference. This, however, is merely an abstraction: both functions are inextricably linked inside the TL431's front end. There is no physical 2.495 V source: the actual internal reference is provided by a 1.2 V Widlar bandgap (transistors T |
https://en.wikipedia.org/wiki/SmartQ%205 | The SmartQ 5 is a budget mobile Internet device manufactured by the Chinese company Smart Devices. It was officially announced 11 February 2009.
Overview
The SmartQ 5 comes with a custom version of Ubuntu Linux installed which is adapted for use with a touchscreen. It uses the LXDE desktop environment.
Ubuntu's main pre-installed applications are:
Midori web browser
FBReader e-book reader
Claws email client
SMPlayer multimedia player
Abiword word processor
Gnumeric spreadsheet
Transmission torrent client
Sonata music player
Pidgin instant messenger
Evince PDF/document reader
rgbPaint painting program
GDebi package installer
PCMan File Manager
It is possible to install another Linux besides the default OS. Several Linux distributions like Mer and a ported Android support the SmartQ 5.
Smart Devices has obtained a Windows CE 6.0 royalty, the OS has been made available on the official site. Although a license from Microsoft needs to be purchased to activate Windows CE.
Specifications
Samsung Mobile Application Processor S3C6410 based on ARM11 core at 667 MHz/800 MHz
128MB DDR 133/333 MHz SDRAM
1GB NAND FLASH (256 MB usable for storage)
AC97 audio codec & PCM 24-bit audio
SoC graphics unit, OpenGL ES 1.1/2.0, 4M triangles/sec @133Mhz (Transform only)
Integrated Wi-Fi 802.11b/g
Integrated Bluetooth 2.0 + EDR
800x480 resolution resistive touchscreen LCD, 4.3", 16.7 million colors
SDHC card slot (up to 32 GB)
Headphone output power up to earphone 40 mW, frequency Response 20 Hz-20.000 Hz SNR 94dB
Internal microphone
USB 2.0 OTG port (480Mbit/s)
Runs Ubuntu Linux
2000mAH rechargeable lithium polymer battery
Dimensions: 120x74x14mm
Weight: 160 g
See also
SmartQ 7
SmartQ V5
SmartQ V7
SmartQ R7 |
https://en.wikipedia.org/wiki/ODE/IM%20correspondence | In mathematical physics, the ODE/IM correspondence is a link between ordinary differential equations (ODEs) and integrable models. It was first found in 1998 by Patrick Dorey and Roberto Tateo. In this original setting it relates the spectrum of a certain integrable model of magnetism known as the XXZ-model to solutions of the one-dimensional Schrödinger equation with a specific choice of potential, where the position coordinate is considered as a complex coordinate.
Since then, such a correspondence has been found for many more ODE/IM pairs.
See also
Bethe ansatz
WKB approximation |
https://en.wikipedia.org/wiki/Isofuran | Isofurans are nonclassic eicosanoids formed nonenzymatically by free radical mediated peroxidation of arachidonic acid. The isofurans are similar to the isoprostanes and are formed under similar conditions, but contain a substituted tetrahydrofuran ring. The concentration of oxygen affects this process; at elevated oxygen concentrations, the formation of isofurans is favored whereas the formation of isoprostanes is disfavored. |
https://en.wikipedia.org/wiki/Mother%20Croatia | Mother Croatia () is the female personification of Croatia and a national emblem of the nation.
Background
The nation of Croatia has historically been portrayed as a motherland, and is often personified as a female figure evoking the traditional woman's role as a mother and nurturer. During the Illyrian movement in the 19th century, many prominent writers and intellectuals used the figure of Mother Croatia to represent the Croat people, especially in favor of nationhood and against Hungarian authority. Writer Mijo Krešić wrote in response to increasing Hungarian threat to the Croatian town Varaždin, "The Hun rejoices, but Mother Croatia laments!"
The phrase has come up in the Croatian Parliament in a way of describing the nation. Once in a speech by in 1861 concerning the struggle against Hungarian hegemony, "That Mother Croatia did not accidentally birth a son, who would in the Hungarian Parliament deny her any independence" (Da hrvatska majka nije po nesreći rodila sina, koji joj je na Ugarskom saboru zaniekao svaku samostalnost). Another time in June 1891, Dr. Milan Amruš spoke of the country, "Mother Croatia is a healthy and energetic mother" (Majka hrvatska je zdrava i čila majka).
Monuments and art
Croatian sculptor Ivan Rendić created several pieces depicting Mother Croatia. One is the tomb of Petar Preradović, which depicts a young woman (representing Mother Croatia) looking solemnly down at his final resting place as she lays her flowers on top. The monument (originally the idea of Croatian writer Franjo Marković), was unveiled on 14 July 1879 to much patriotic fanfare. Another piece by Rendić is the statue of Ante Starčević in front of St. Mirko's Church in Zagreb. At the base of the statue is a woman (the personification of Croatia) dressed as a warrior, with clenched fists and a defiant face, her gaze fixed ahead.
In painter Ferdo Quiquerez's Antemurale Christianitatis ("Bulwark of Christendom"), Croatia is portrayed as a woman holding a sword and |
https://en.wikipedia.org/wiki/Tamatebako%20%28origami%29 | The is an origami model named after the tamatebako of Japanese folk tale. It is a modular cube design that can be opened from any side. If more than one face of the model is opened, the cube falls apart and cannot easily be reconstructed. The model, and the directions for creating it, had been lost for centuries and only recently rediscovered.
Drawings from a three volume set of wood carvings, published in 1743 by Ōoka Shunboku, featured a colored origami cube. In 1993, Yasuo Koyanagi identified the cube as the Tamatebako, and the model was published in the book "Koten-ni-miri-origami" by Satoshi Tagaki. The popular origami historian, Masao Okamura then was able to reconstruct the model, and by comparison to other traditional works, verify the model's authenticity.
Basic folding instructions
Valley-fold a square into thirds between both pairs of edges, creating nine sub-squares. Cut a diagonal X across the entire center square, pinwheel-fold the outer edges, and fold the protruding pinwheel flaps inward, interleaving them to produce a multilayered square with the top woven together. Fold outward the triangular flaps cut from the center square. This creates one face of the cube; the entire cube requires six identical modules.
For each module, tuck one opposing pair of cut flaps into the pockets at the base of the pinwheel, and insert the remaining pair of cut flaps into the pockets of two other faces to assemble the entire cube. The resulting tamatebako can be opened from any face by either unfolding the pinwheel or gently pulling one face completely off the rest of the cube.
Variations
The cube can also be assembled by gluing together the undersides of the flaps of adjacent faces. When the glue is dry, tuck the glued flaps into the pinwheel pockets in the same manner as above, with each face having one pair of flaps tucked into itself and the other two tucked into the adjacent faces. Like the original version, the glued cube can be opened from any face by |
https://en.wikipedia.org/wiki/Deep%20content%20inspection | Deep content inspection (DCI) is a form of network filtering that examines an entire file or MIME object as it passes an inspection point, searching for viruses, spam, data loss, key words or other content level criteria. Deep Content Inspection is considered the evolution of Deep Packet Inspection with the ability to look at what the actual content contains instead of focusing on individual or multiple packets. Deep Content Inspection allows services to keep track of content across multiple packets so that the signatures they may be searching for can cross packet boundaries and yet they will still be found. An exhaustive form of network traffic inspection in which Internet traffic is examined across all the seven OSI ISO layers, and most importantly, the application layer.
Background
Traditional inspection technologies are unable to keep up with the recent outbreaks of widespread attacks. Unlike shallow inspection methods such as Deep Packet Inspection (DPI), where only the data part (and possibly also the header) of a packet are inspected, Deep Content Inspection (DCI)-based systems are exhaustive, such that network traffic packets are reassembled into their constituting objects, un-encoded and/or decompressed as required, and finally presented to be inspected for malware, right-of-use, compliance, and understanding of the traffic's intent. If this reconstruction and comprehension can be done in real-time, then real-time policies can be applied to traffic, preventing the propagation of malware, spam and valuable data loss. Further, with DCI, the correlation and comprehension of the digital objects transmitted in many communication sessions leads to new ways of network performance optimization and intelligence regardless of protocol or blended communication sessions.
Historically, DPI was developed to detect and prevent intrusion. It was then used to provide Quality of Service where the flow of network traffic can be prioritized such that latency-sensitive tra |
https://en.wikipedia.org/wiki/Joint%20constraints | Joint constraints are rotational constraints on the joints of an artificial system. They are used in an inverse kinematics chain, in fields including 3D animation or robotics. Joint constraints can be implemented in a number of ways, but the most common method is to limit rotation about the X, Y and Z axis independently. An elbow, for instance, could be represented by limiting rotation on X and Z axis to 0 degrees, and constraining the Y-axis rotation to 130 degrees.
To simulate joint constraints more accurately, dot-products can be used with an independent axis to repulse the child bones orientation from the unreachable axis. Limiting the orientation of the child bone to a border of vectors tangent to the surface of the joint, repulsing the child bone away from the border, can also be useful in the precise restriction of shoulder movement. |
https://en.wikipedia.org/wiki/Iland | iland Internet Solutions was a provider of hosted cloud infrastructure as a service for production business applications, disaster recovery and business continuity, testing and development, and software as a service enablement for independent software vendors. 11:11 Systems agreed to buy iland in December 2021. When the merger completed in January 2022, all of iland's services and assets were transferred to 11:11.
At the time, iland was a Premier-level partner in the VMware Service Provider Program (VSPP).
Founded in 1995, iland offered its services from high availability hubs specifically designed for cloud infrastructure in Boston, Washington D.C., Houston, Los Angeles, Dallas, Manchester, London, Amsterdam, Singapore, Melbourne, and Sydney. iland is a Premier-level partner in the VMware Service Provider Program (VSPP).
iland also provided traditional colocation and global hybrid cloud services, hosting infrastructure (IaaS), disaster recovery (DRaaS), and backup as a service (BaaS). Headquartered in Houston, Texas and London, UK, iland delivers cloud services from its data centers throughout the Americas, Europe, Asia and Australia.
iland services
iland provided cloud-based disaster recovery and business continuity services.
Other services included desktop virtualization integrated with a company's overall business continuity and disaster recovery plan, a cloud environment specifically for software as a service (SaaS) providers and merged virtual cloud and physical colocation center servers for custom enterprise configurations. It provides a data replication service for Dell EqualLogic customers. |
https://en.wikipedia.org/wiki/Wall.fm | Wall.fm is an online service for people to build and host social networking services, powered by Oxwall software. Wall.fm allows users over 18 years old to register a free account and create custom social networking websites. The site creation process does not involve any coding, and consists of only two steps.
The distinctive Wall.fm features are user roles (member access permissions), customizable themes, activity newsfeed, website/profile/content privacy, monetization pack. One of its main competitive advantages is that the service is built on an open source platform, which means a certain degree of freedom for site owners.
Wall.fm offers three plans: Starter, Pro and Ultimate. Plans offer different feature sets, disk space and bandwidth, individual support and vendor's branding removal. Every plan offers free trial.
History
Wall.fm was launched as WackWall in February 2010. The second version of WackWall, which was later renamed to Wall.fm, was powered by OpenWack software that eventually evolved into Oxwall. Wall.fm exited beta in October 2010, and started introducing paid plans and changes to free accounts, such as displaying the vendor's ads across the free plan sites, and including a site monetization pack into Ultimate plan features. On May 15, 2011 Wall.fm updated their Terms of Use limiting the use of the service to persons over 18 years old, and introducing regulations for sites intended for use by children under 13 years old. On February 27, 2012 Wall.fm announced significant changes in their pricing policy and user account interface, making subscription plans more affordable although limited in disk space/bandwidth, and site account management more user-friendly. As of May 2011, over 3000 sites are built with Wall.fm service each month.
As of January 2013, Wall.fm only offers free site registration by invites.
Features
Wall.fm provides all the basic functionality required to build a social website: user roles, photo/video sharing, chat, blogs, f |
https://en.wikipedia.org/wiki/In%20Mortal%20Hands | In Mortal Hands: A Cautionary History of the Nuclear Age is a 2009 book by Stephanie Cooke. The book explains why nuclear energy failed to develop in the way its planners hoped, and explores the relationship between the military and civilian sides of nuclear energy. In the book, Cooke argues that we are not close to solving the nuclear waste problem, and that "the billions spent by government on nuclear over the past sixty years crowded out other energy options". The book suggests that there are practical reasons why nuclear reactors are unlikely to provide a solution to the global climate change problem.
In Mortal Hands has been the subject of several media interviews with Cooke.
Stephanie Cooke has written about the nuclear industry since the 1980s. She is currently an editor for the Energy Intelligence Group publication, Nuclear Intelligence Weekly and is a contributor to the Bulletin of the Atomic Scientists.
See also
List of books about nuclear issues
Nuclear power debate |
https://en.wikipedia.org/wiki/Rough%20set | In computer science, a rough set, first described by Polish computer scientist Zdzisław I. Pawlak, is a formal approximation of a crisp set (i.e., conventional set) in terms of a pair of sets which give the lower and the upper approximation of the original set. In the standard version of rough set theory (Pawlak 1991), the lower- and upper-approximation sets are crisp sets, but in other variations, the approximating sets may be fuzzy sets.
Definitions
The following section contains an overview of the basic framework of rough set theory, as originally proposed by Zdzisław I. Pawlak, along with some of the key definitions. More formal properties and boundaries of rough sets can be found in Pawlak (1991) and cited references. The initial and basic theory of rough sets is sometimes referred to as "Pawlak Rough Sets" or "classical rough sets", as a means to distinguish from more recent extensions and generalizations.
Information system framework
Let be an information system (attribute–value system), where is a non-empty, finite set of objects (the universe) and is a non-empty, finite set of attributes such that for every . is the set of values that attribute may take. The information table assigns a value from to each attribute and object in the universe .
With any there is an associated equivalence relation :
The relation is called a -indiscernibility relation. The partition of is a family of all equivalence classes of and is denoted by (or ).
If , then and are indiscernible (or indistinguishable) by attributes from .
The equivalence classes of the -indiscernibility relation are denoted .
Example: equivalence-class structure
For example, consider the following information table:
{| class="wikitable" style="text-align:center; width:30%" border="1"
|+ Sample Information System
! Object !! !! !! !! !!
|-
!
| 1 || 2 || 0 || 1 || 1
|-
!
| 1 || 2 || 0 || 1 || 1
|-
!
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https://en.wikipedia.org/wiki/Benign%20fasciculation%20syndrome | Benign fasciculation syndrome (BFS) is characterized by fasciculation (twitching) of voluntary muscles in the body. The twitching can occur in any voluntary muscle group but is most common in the eyelids, arms, hands, fingers, legs, and feet. The tongue can also be affected. The twitching may be occasional to continuous. BFS must be distinguished from other conditions that include muscle twitches.
Signs and symptoms
The main symptom of benign fasciculation syndrome is focal or widespread involuntary muscle activity (fasciculation). The benign twitches usually have a constant location.
Other common symptoms are generalized fatigue or weakness, paraesthesia or numbness, and muscle cramping or spasms. Anxiety and somatic symptom disorders and symptoms are commonly reported. Muscle stiffness may also be present; if muscle weakness is not also present, and cramps are more severe, the stiffness may be categorized instead as cramp fasciculation syndrome. Cramp fasciculation is a variant of BFS which presents with muscle pain and exercise intolerance.
BFS symptoms are typically not accompanied by severe muscle weakness, and are typically present when the muscle is at rest. Individuals with BFS may have perceived weakness which is the sensation of a fatigued limb, but is not true clinical weakness. Fasciculations can move from one part of the body to another.
Causes
The precise cause of BFS is unknown. It is not known if it is a disease of the motor nerves, the muscles, or the neuromuscular junction.
Health anxiety disorder may be a cause among individuals who become concerned they have a motor neuron disease; this persistent concern is a psychiatric condition mostly noted among healthcare professionals and doctors. An association with anxiety level is established; BFS is reportedly found among "anxious medical students" and clinicians under the age of 40, and this phenomenon known as "fasciculation anxiety syndrome" is reinforced by access to information on the intern |
https://en.wikipedia.org/wiki/Texas%20Instruments%20AR7 | The Texas Instruments AR7 or TI-AR7 is a fully integrated single-chip ADSL CPE access router solution. The AR7 combines a MIPS32 processor, a DSP-based digital transceiver, and an ADSL analog front end.
Ownership history
In 2007, TI sold its DSL business to Infineon.
In 2009, Infineon Technologies spins off its wireline division to Lantiq.
On November 6, 2009, Lantiq announced that it became a standalone company.
Features
Integrated high performance MIPS 4KEc 32-Bit RISC processor
ADSL PHY subsystem based on TI C62x DSP, with integrated transceiver, codec, line driver, and line receiver
Hardware accelerated ATM Segmentation and Reassembly (SAR)
Integrated IEEE 802.3 PHY
Two IEEE 802.3 MACs with integrated Media Independent Interface (MII) and Quality of Service (QoS)
Integrated USB 1.1 compliant transceiver (slave only)
Two VLYNQ interfaces for compatible high-speed expansion devices
Two 16c550 compatible UARTs
EJTAG, GPIO and "Flexible Serial Interface" (FSER) interfaces
4 KiB PROM (0xBFC00000) and 4KiB RAM (0x80000000) on the chip for boot purposes
Physical package of a 324 BGA with 1.0-mm ball pitch
Options
AR7DB
AR7RD
AR7WRD (TNETD7300GDU) is an AR7 option with an interface for WiFi card.
AR7VWI : DSL + VoIP + Wireless
AR7VW
AR7WI
AR7V : DSL + VoIP
The Adam2 bootloader
The Pspboot bootloader
Devices based on the Texas Instruments AR7
Actiontec GT701
Acorp W400G/W422G
Asus AAM6010EV : TNETD7300GDU, 2Mb FLASH, 8Mb SDRAM
AVM Fritz!Box
Aztech DSL-600E: 2Mb FLASH, 8Mb SDRAM
Aztech DSL600ER: 2Mb FLASH, 8Mb SDRAM, 88E6060 Switch
Aztech DSL600EW: 4Mb FLASH, 16Mb SDRAM, 88E6060 Switch, TNETW1130
D-Link DSL-xxxT (like 300T)
D-Link DVA-G3342SB (DSL board only)
ECI B-FOCuS combo 352+, B-FOCuS Router 312+A
devolo dsl+ 1100 duo, dsl+ 1100 LAN
Efficient Networks, Inc / ENI SpeedStream 5100
Huawei WA1003A
LevelOne FBR-1416A: 2Mb FLASH, 8Mb SDRAM, 88E6060 Switch
Linksys ADSL2MUE 4MB Flash, 16MB ram, USB + 1 Ethernet only
Linksys AG241 |
https://en.wikipedia.org/wiki/Global%20coordination%20level | Global coordination level (GCL) is a computational method that evaluates the system-wide dependency in multivariate data, by calculating the distance correlation between random subsets of the variables. Originally applied to gene expression data, GCL assesses the level of coordination between genes, which are fundamentally linked in performing tasks and biological functions. Unlike traditional methods that require precise knowledge of pairwise interactions between genes, GCL can evaluate coordination without such information. The GCL value of zero signifies independent gene expression, while values above zero indicate gene-to-gene regulatory interactions. For instance, when GCL is applied to known genetic pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, it yields significantly positive values, while random subsets of genes or mock pathways with similar gene expression levels show very low GCL values. Additionally, GCL can be useful in analyzing high-dimensional ecological and biochemical dynamics.
Introduction
Genes interact with each other in a complex structure known as the gene regulatory network, which plays a crucial role in implementing various biological functions and performing different tasks within cells. However, inferring the precise pairwise interactions of the gene regulatory network remains challenging due to the large number of functional genes and the inherent stochasticity of these systems. Despite these challenges, certain features of the gene regulatory network can still be extracted without fully inferring all the interactions. For instance, the network connectivity, which refers to the density of actual gene-gene interactions compared to all possible interactions, may have important implications for general cellular processes.
Method description
The calculation of the Conditional Likelihood (CL) is based on multivariate dependencies among genes in a given cohort of cells. This involves a repeated procedure of randomly |
https://en.wikipedia.org/wiki/Newt%20Heisley | Newton Foust Heisley (November 9, 1920 – May 14, 2009) was an American commercial artist who was responsible for the design of the POW/MIA flag adopted by the National League of Families, and officially recognized by the United States Congress in relation to the Vietnam War POW/MIA issue "as the symbol of our Nation's concern and commitment to resolving as fully as possible the fates of Americans still prisoner, missing and unaccounted for in Southeast Asia, thus ending the uncertainty for their families and the Nation".
Biography
Heisley was born in Williamsport, Pennsylvania, on November 9, 1920. He lived with his grandparents for much of his youth, following the death of his mother when he was four-years old. He attended Syracuse University, graduating with a degree in fine arts, after which he worked as a graphic artist for the Pittsburgh Post-Gazette. He enlisted during World War II, serving as a pilot in the United States Army Air Forces.
Graphic design and the POW/MIA flag
After the completion of his military service, Heisley spent more than two decades working at advertising firms in the New York City area. In 1971, a New Jersey-based agency he worked for assigned him to create a flag for their client Annin & Company, the largest flag manufacturer in the United States, which had been given the task to create the flag by Mary Hoff, the wife of Lt. Commander Michael Hoff U.S.N., (a service member missing in action) and a member of the National League of Families of American Prisoners and Missing in Southeast Asia.
The image he designed uses black-and-white images of the silhouette of a man in profile with his head bowed in the foreground with a guard tower and barbed wire behind him. Heisley used the image of his son Jeffrey, a 24-year-old member of the United States Marine Corps, who had just returned from basic training where he was preparing to be shipped to Vietnam, returning from his training appearing sickly after a bout of hepatitis. "You Are Not For |
https://en.wikipedia.org/wiki/Partial%20equilibrium | In economics, partial equilibrium is a condition of economic equilibrium which analyzes only a single market, ceteris paribus (everything else remaining constant) except for the one change at a time being analyzed. In general equilibrium analysis, on the other hand, the prices and quantities of all markets in the economy are considered simultaneously, including feedback effects from one to another, though the assumption of ceteris paribus is maintained with respect to such things as constancy of tastes and technology.
Mas-Colell, Whinston & Green's widely used graduate textbook says, "Partial equilibrium models of markets, or of systems of related markets, determine prices, profits, productions, and the other variables of interest adhering to the assumption that there are no feedback effects from these endogenous magnitudes to the underlying demand or cost curves that are specified in advance." General equilibrium analysis, in contrast, begins with tastes, endowments, and technology being fixed, but takes into account feedback effects between the prices and quantities of all goods in the economy.
The supply and demand model originated by Alfred Marshall is the paradigmatic example of a partial equilibrium model. The clearance of the market for some specific goods is obtained independently from prices and quantities in other markets. In other words, the prices of all substitute goods and complement goods, as well as income levels of consumers, are taken as given. This makes analysis much simpler than in a general equilibrium model, which includes an entire economy.
Consider, for example, the effect of a tariff on imported French wine. Partial equilibrium would look at just that market, and show that the price would rise. It would ignore the fact that if French wine became more expensive, demand for domestic wine would rise, pushing up the price of domestic wine, which would feed back into the market for French wine. If the feedback were included, the higher |
https://en.wikipedia.org/wiki/Cornus%20mas | Cornus mas, commonly known as cornel (also the Cornelian cherry, European cornel or Cornelian cherry dogwood), is a species of shrub or small tree in the dogwood family Cornaceae native to Western Europe, Southern Europe, and Southwestern Asia.
Description
It is a medium to large deciduous shrub or small tree growing to 5–12 m tall, with dark brown branches and greenish twigs. The leaves are opposite, 4–10 cm long and 2–4 cm broad, with an ovate to oblong shape and an entire margin. The flowers are small (5–10 mm in diameter), with four yellow petals, produced in clusters of 10–25 together in the late winter (between February and March in the UK), well before the leaves appear. The fruit is an oblong red drupe 2 cm long and 1.5 cm in diameter, containing a single seed.
Uses
Fruit
The fruits are red berries. When ripe on the plant, they bear a resemblance to coffee berries, and ripen in mid- to late summer. The fruit is edible and widely popular in Iran, where it is believed to have various medicinal properties and provide health benefits. It is also used in Eastern Europe, the UK, and British Columbia, Canada, but the unripe fruit is astringent. When ripe, the fruit is dark ruby red or a bright yellow. It has an acidic flavor which is best described as a mixture of cranberry and sour cherry. It is mainly used for making jam. It is widely used in Azerbaijan to make pickles, added to rice or make beverages. In Armenia, Cornus berries are used to make vodka. In Romania and Moldova, the berries are used to make an alcoholic beverage known as cornată. In Bulgaria the berries are widely used to make Kompot.
The fruit of Cornus mas (together with the fruit of C. officinalis) has a history of use in traditional Chinese medicine in which it is known as , and used to retain the jing.
Flowers
The species is also grown as an ornamental plant for its late winter yellow flowers, which open earlier than those of Forsythia. While Cornus mas flowers are not as large and vi |
https://en.wikipedia.org/wiki/Circle%20of%20competence | A circle of competence is the subject area which matches a person's skills or expertise. The concept was developed by Warren Buffett and Charlie Munger as what they call a mental model, a codified form of business acumen, concerning the investment strategy of limiting one's financial investments in areas where an individual may have limited understanding or experience, while concentrating in areas where one has the greatest familiarity. The strategy emphasizes the importance of aligning one's subjective assessment with actual competence. Buffett summarized the concept in the motto, "Know your circle of competence, and stick within it. The size of that circle is not very important; knowing its boundaries, however, is vital."
In his 1996 letter to Berkshire Hathaway, Buffett further expanded:
What an investor needs is the ability to correctly evaluate selected businesses. Note that word 'selected': You don't have to be an expert on every company, or even many. You only have to be able to evaluate companies within your circle of competence.
Sampan Nettayanun from Naresuan University traces the concept, if not the terminology, as far back as Andrew Carnegie, in his decision to concentrate on iron and steel, writing "My advice to young men would be not only to concentrate their whole time and attention on the one business in life in which they engage, but to put every dollar of their capital into it."
Operating within one's circle of competence may be compared with those who act over-confidently. For example, institutional investors who have been successful in the past are more likely to attribute their success to their own abilities, rather than external forces, and are therefore more likely to make investments in areas outside their circle of competence. The strategy of operating within their individual circles has been cited as the reason both Buffett and Munger avoided investing in the technology sector.
The breadth of any individual's circle of competence may b |
https://en.wikipedia.org/wiki/Matrix%20polynomial | In mathematics, a matrix polynomial is a polynomial with square matrices as variables. Given an ordinary, scalar-valued polynomial
this polynomial evaluated at a matrix A is
where I is the identity matrix.
A matrix polynomial equation is an equality between two matrix polynomials, which holds for the specific matrices in question. A matrix polynomial identity is a matrix polynomial equation which holds for all matrices A in a specified matrix ring Mn(R).
Characteristic and minimal polynomial
The characteristic polynomial of a matrix A is a scalar-valued polynomial, defined by . The Cayley–Hamilton theorem states that if this polynomial is viewed as a matrix polynomial and evaluated at the matrix A itself, the result is the zero matrix: . The characteristic polynomial is thus a polynomial which annihilates A.
There is a unique monic polynomial of minimal degree which annihilates A; this polynomial is the minimal polynomial. Any polynomial which annihilates A (such as the characteristic polynomial) is a multiple of the minimal polynomial.
It follows that given two polynomials P and Q, we have if and only if
where denotes the jth derivative of P and are the eigenvalues of A with corresponding indices (the index of an eigenvalue is the size of its largest Jordan block).
Matrix geometrical series
Matrix polynomials can be used to sum a matrix geometrical series as one would an ordinary geometric series,
If I − A is nonsingular one can evaluate the expression for the sum S.
See also
Latimer–MacDuffee theorem
Matrix exponential
Matrix function
Notes |
https://en.wikipedia.org/wiki/Transverse%20occipital%20sulcus | The transverse occipital sulcus is a structure in the occipital lobe.
The transverse occipital sulcus is continuous with the posterior end of the occipital ramus of the intraparietal sulcus, and runs across the upper part of the lobe, a short distance behind the parietooccipital fissure. |
https://en.wikipedia.org/wiki/Lymphokine | Lymphokines are a subset of cytokines that are produced by a type of immune cell known as a lymphocyte. They are protein mediators typically produced by T cells to direct the immune system response by signaling between its cells. Lymphokines have many roles, including the attraction of other immune cells, including macrophages and other lymphocytes, to an infected site and their subsequent activation to prepare them to mount an immune response. Circulating lymphocytes can detect a very small concentration of lymphokine and then move up the concentration gradient towards where the immune response is required. Lymphokines aid B cells to produce antibodies.
Important lymphokines secreted by the T helper cell include:
Interleukin 2
Interleukin 3
Interleukin 4
Interleukin 5
Interleukin 6
Granulocyte-macrophage colony-stimulating factor
Interferon-gamma |
https://en.wikipedia.org/wiki/List%20of%20restriction%20enzyme%20cutting%20sites%3A%20Bsp%E2%80%93Bss | This article contains a list of the most studied restriction enzymes whose names start with Bsp to Bss inclusive. It contains approximately 180 enzymes.
The following information is given:
Whole list navigation
Restriction enzymes
Bsp
Bsr - Bss
Notes
Biotechnology
Restriction enzyme cutting sites
Restriction enzymes |
https://en.wikipedia.org/wiki/Sarcodon%20imbricatus | Sarcodon imbricatus, commonly known as the shingled hedgehog or scaly hedgehog, is a species of tooth fungus in the order Thelephorales. The mushroom is edible. Many sources report it has a bitter taste, but others have found it delicious and suspect that the bitter specimens may be similar related species. The mushroom has a large, brownish cap with large brown scales and may reach 30 cm (12 in) in diameter. On the underside it sports greyish, brittle teeth instead of gills, and has white flesh. Its spore print is brown. It is associated with spruce (Picea), appearing in autumn. It ranges throughout North America and Europe, although collections from the British Isles are now assigned to the similar species Sarcodon squamosus.
Taxonomy
The Swedish botanist Olof Celsius reported in 1732 that Sarcodon imbricatus occurred in the vicinity of Uppsala, and Carl Linnaeus wrote of it in his 1737 work Flora lapponica. It was one of the species initially described by Linnaeus, as Hydnum imbricatum, in the second volume of his Species Plantarum in 1753. The specific epithet is the Latin imbricatus meaning "tiled" or "with overlapping tiles". It was then placed in the genus Sarcodon by Finnish mycologist Petter Adolf Karsten in 1881.
For many years, Sarcodon imbricatus was described associated with both spruce and pine, although the latter forms were smaller and noted to be more palatable by mushroom hunters in Norway. Furthermore, the mushroom has been used as a source of pigment and collectors noted that fresh specimens collected under pine yielded pigment, but only old ones collected under spruce. Molecular analysis of the DNA revealed the two forms to be distinct genetically, and thus populations of what had been described as S. imbricatus were now assigned to Sarcodon squamosus, which includes collections in the British Isles and the Netherlands.
Description
The mushrooms, or fruiting bodies, can be quite large in size. The brownish or buff cap measures up to 30 cm (1 |
https://en.wikipedia.org/wiki/Quadric%20%28algebraic%20geometry%29 | In mathematics, a quadric or quadric hypersurface is the subspace of N-dimensional space defined by a polynomial equation of degree 2 over a field. Quadrics are fundamental examples in algebraic geometry. The theory is simplified by working in projective space rather than affine space. An example is the quadric surface
in projective space over the complex numbers C. A quadric has a natural action of the orthogonal group, and so the study of quadrics can be considered as a descendant of Euclidean geometry.
Many properties of quadrics hold more generally for projective homogeneous varieties. Another generalization of quadrics is provided by Fano varieties.
Property of quadric
By definition, a quadric X of dimension n over a field k is the subspace of defined by q = 0, where q is a nonzero homogeneous polynomial of degree 2 over k in variables . (A homogeneous polynomial is also called a form, and so q may be called a quadratic form.) If q is the product of two linear forms, then X is the union of two hyperplanes. It is common to assume that and q is irreducible, which excludes that special case.
Here algebraic varieties over a field k are considered as a special class of schemes over k. When k is algebraically closed, one can also think of a projective variety in a more elementary way, as a subset of defined by homogeneous polynomial equations with coefficients in k.
If q can be written (after some linear change of coordinates) as a polynomial in a proper subset of the variables, then X is the projective cone over a lower-dimensional quadric. It is reasonable to focus attention on the case where X is not a cone. For k of characteristic not 2, X is not a cone if and only if X is smooth over k. When k has characteristic not 2, smoothness of a quadric is also equivalent to the Hessian matrix of q having nonzero determinant, or to the associated bilinear form b(x,y) = q(x+y) – q(x) – q(y) being nondegenerate. In general, for k of characteristic not 2, the rank of |
https://en.wikipedia.org/wiki/Transient%20photocurrent | Transient photocurrent (TPC) is a measurement technique, typically employed in the physics of thin film semiconductors. TPC allows to study the time-dependent (on a microsecond time scale) extraction of charges generated by photovoltaic effect in semiconductor devices, such as solar cells.
A semiconductor is sandwiched between two extracting electrodes. When it is excited with a short pulse of light (as short as 100 femtoseconds), the photogenerated charges are extracted on the electrodes, resulting in a current, which is detected by an oscilloscope in form of voltage across a resistor. Since the excitation pulse is square, there are two ways to measure TPC: in a “light on” and a “light off” positions. In a “Light on”, the signal is recorded as soon as the excitation pulse is switched on, allowing to observe the build-up of charges on the electrode after the start of excitation. “Light off” measurements show how the charges decay after the pulse is switched off.
In contrast to transient photovoltage, TPC measurements are conducted under short circuit condition and yield information about extractable charges, charge recombination and density of states. Quite often, TPC measurements help to build “drift-diffusion” model which reflects trapping and detrapping of the photogenerated charges and the quality of contact between different layers.
TPC allows varying different measurement parameters, such as intensity or length of the light pulse, applied voltage, etc.
See also
Time resolved microwave conductivity
Photoconductance decay |
https://en.wikipedia.org/wiki/Terminal%20bar%20%28histology%29 | Terminal bar is a histological term given to the unresolved group of junctional complexes that attach adjacent epithelial cells on their lateral surfaces: the zonula occludens, zonula adherens, macula adherens and macula communicans.
Using light microscopy, the terminal bar appears as a bar or spot at the apical surface of the cell, wherein the structures listed cannot be resolved. With electron microscopy, it can be visually disseminated into these structures.
The terminal bar is located on the lateral surface of epithelial cells, where the lateral surface meets the apical surface. It should not be confused with the terminal web, which is an actinous web underlying microvilli on specialized epithelial cells. |
https://en.wikipedia.org/wiki/Branchiostegal%20lung | A branchiostegal lung is a respiration organ used by some air-breathing arthropods. It is one of the most significant adaptations of some crabs and hermit crabs such as the coconut crab to their terrestrial habitats.
The branchiostegal (gill) tissue is supported by folds or other mechanisms to increase surface area and are of a similar tissue to that normally found in gills. In this case, the lung is more suited to the absorption of oxygen from air, rather than water.
Instead of branchiostegal lungs, some terrestrial hermit crabs (Coenobita) possess multiple gills and small lungs, with other varieties of gas diffusion methods supporting the transition from aquatic to terrestrial dwelling.
The developmental shift from water diffusion "gills" to air perfusion "lungs" may have been related to the need for reduced rates of water loss in air. |
https://en.wikipedia.org/wiki/Michael%20R.%20Hayden | Michael R. Hayden, (born 1951) is a Killam Professor of Medical Genetics at the University of British Columbia, the highest honour UBC can confer on any faculty member. Only four such awards have ever been conferred in the Faculty of Medicine. Dr. Hayden is also Canada Research Chair in Human Genetics and Molecular Medicine. Hayden is best known for his research in Huntington disease (HD).
He is a senior scientist and former director of the Centre for Molecular Medicine and Therapeutics (CMMT) in Vancouver, British Columbia, Canada; a genetic research centre within UBC's Faculty of Medicine and affiliated with the BC Children's Hospital Research Institute and the BC Children's Hospital Foundation, which he founded. He was also the Program Director of the Translational Laboratory in Genetic Medicine in Singapore from 2011-2020, and was appointed as the President of Global R&D and Chief Scientific Officer at Teva Pharmaceutical Industries from 2012–2017. During this time, approximately 35 new products were approved in major markets with many for diseases of the central nervous system and led the approval of Austedo for chorea in HD, the second drug ever to be approved for HD. In 2015, Teva R&D was recognized as one of the 10 most exciting innovators in Pharma by IDEA Pharma and in 2017, Teva R&D ranked top of the industry for CNS development and clinical trial success by Pharma Intelligence.
Hayden is the most cited author in the world for Huntington disease and ABCA1, and has authored over 900 publications and invited submissions (Google Scholar citations 99,672, h-index 160, i10-index 766; Web of Science citations 65,327, h-index 123).
In 2007, he received the Prix Galien which recognizes the outstanding contribution of a researcher to Canadian pharmaceutical research; in 2008, recognition from the Canadian Institutes of Health Research (CIHR) as Canada's Health Researcher of the Year: CIHR Michael Smith Prizes in Health Research. In 2010, he was awarded Member |
https://en.wikipedia.org/wiki/Immunodominance | Immunodominance is the immunological phenomenon in which immune responses are mounted against only a few of the antigenic peptides out of the many produced. That is, despite multiple allelic variations of MHC molecules and multiple peptides presented on antigen presenting cells, the immune response is skewed to only specific combinations of the two. Immunodominance is evident for both antibody-mediated immunity and cell-mediated immunity. Epitopes that are not targeted or targeted to a lower degree during an immune response are known as subdominant epitopes. The impact of immunodominance is immunodomination, where immunodominant epitopes will curtail immune responses against non-dominant epitopes.
Antigen-presenting cells such as dendritic cells, can have up to six different types of MHC molecules for antigen presentation. There is a potential for generation of hundreds to thousands of different peptides from the proteins of pathogens. Yet, the effector cell population that is reactive against the pathogen is dominated by cells that recognize only a certain class of MHC bound to only certain pathogen-derived peptides presented by that MHC class.
Antigens from a particular pathogen can be of variable immunogenicity, with the antigen that stimulates the strongest response being the immunodominant one. The different levels of immunogenicity amongst antigens forms what is known as dominance hierarchy.
Mechanism
CTL immunodominance
The mechanisms of immunodominance are very poorly understood. What determines cytotoxic T lymphocyte (CTL) immunodominance can be a number of factors, many of which are debated. Of these, one in particular focuses on the timing of CTL clonal expansion. The dominant CTLs that arise were activated sooner so therefore proliferate faster than subdominant CTLs that were activated later, thus resulting in a greater number of CTLs for that immunodominant epitope. This can be in concordance with an additional theory which states that immunodomina |
https://en.wikipedia.org/wiki/Krawtchouk%20matrices | In mathematics, Krawtchouk matrices are matrices whose entries are values of Krawtchouk polynomials at nonnegative integer points. The Krawtchouk matrix K(N) is an matrix. The first few Krawtchouk matrices are:
Definition
In general, for positive integer , the entries are given by the generating function:
where the row and column indices and run from to . Explicitly:
or in terms of the Krawtchouk polynomials:
The values of a Krawchouk matrix can also be calculated using a recurrence relation. Filling the top row with ones and the rightmost column with alternating binomial coefficients, the other entries are each given by the sum of the neighbouring entries to the top, topright and right.
Properties
The Krawtchouk polynomials are orthogonal with respect to symmetric binomial distributions, .
As a transformation, a Krawtchouk matrix is an involution up to scaling:
Krawchouk matrices have an LDU decomposition involving triangular Pascal matrices and a diagonal matrix of the powers of 2.
The eigenvalues are , and the determinant is .
See also
Krawtchouk polynomial
Pascal matrix |
https://en.wikipedia.org/wiki/Manava | Manava (c. 750 BC – 690 BC) is an author of the Hindu geometric text of Sulba Sutras.
The Manava Sulbasutra is not the oldest (the one by Baudhayana is older), nor is it one of the most important, there being at least three Sulbasutras which are considered more important. Historians place his lifetime at around 750 BC.
Manava would have not have been a mathematician in the sense that we would understand it today. Nor was he a scribe who simply copied manuscripts like Ahmes. He would certainly have been a man of very considerable learning but probably not interested in mathematics for its own sake, merely interested in using it for religious purposes. Undoubtedly he wrote the Sulbasutra to provide rules for religious rites and it would appear almost a certainty that Manava himself would be a Hindu priest.
The mathematics given in the Sulbasutras is there to enable accurate construction of altars needed for sacrifices. It is clear from the writing that Manava, as well as being a priest, must have been a skilled craftsman.
Manava's Sulbasutra, like all the Sulbasutras, contained approximate constructions of circles from rectangles, and squares from circles, which can be thought of as giving approximate values of π. There appear therefore different values of π throughout the Sulbasutra, essentially every construction involving circles leads to a different such approximation. The paper of R.C. Gupta is concerned with an interpretation of verses 11.14 and 11.15 of Manava's work which give π = 25/8 = 3.125.
External links |
https://en.wikipedia.org/wiki/Abstract%20factory%20pattern | The abstract factory pattern in software engineering is a design pattern that provides a way to create families of related objects without imposing their concrete classes, by encapsulating a group of individual factories that have a common theme without specifying their concrete classes. According to this pattern, a client software component creates a concrete implementation of the abstract factory and then uses the generic interface of the factory to create the concrete objects that are part of the family. The client does not know which concrete objects it receives from each of these internal factories, as it uses only the generic interfaces of their products. This pattern separates the details of implementation of a set of objects from their general usage and relies on object composition, as object creation is implemented in methods exposed in the factory interface.
Use of this pattern enables interchangeable concrete implementations without changing the code that uses them, even at runtime. However, employment of this pattern, as with similar design patterns, may result in unnecessary complexity and extra work in the initial writing of code. Additionally, higher levels of separation and abstraction can result in systems that are more difficult to debug and maintain.
Overview
The abstract factory design pattern is one of the 23 patterns described in the 1994 Design Patterns book. It may be used to solve problems such as:
How can an application be independent of how its objects are created?
How can a class be independent of how the objects that it requires are created?
How can families of related or dependent objects be created?
Creating objects directly within the class that requires the objects is inflexible because doing so commits the class to particular objects and makes it impossible to change the instantiation later independently from the class without having to change it. It prevents the class from being reusable if other objects are required, and it |
https://en.wikipedia.org/wiki/Homojunction | A homojunction is a semiconductor interface that occurs between layers of similar semiconductor material; these materials have equal band gaps but typically have different doping. In most practical cases a homojunction occurs at the interface between an n-type (donor doped) and p-type (acceptor doped) semiconductor such as silicon, this is called a p–n junction.
This is not a necessary condition as the only requirement is that the same semiconductor (same band gap) is found on both sides of the junction, in contrast to a heterojunction. An n-type to n-type junction, for example, would be considered a homojunction even if the doping levels are different.
The different doping level will cause band bending, and a depletion region will be formed at the interface, as shown in the figure to the right.
See also
Transistor
p–n junction
Band bending
Doping (semiconductor)
Semiconductor structures |
https://en.wikipedia.org/wiki/Basidiomycota | Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basidiomycota includes these groups: agarics, puffballs, stinkhorns, bracket fungi, other polypores, jelly fungi, boletes, chanterelles, earth stars, smuts, bunts, rusts, mirror yeasts, and Cryptococcus, the human pathogenic yeast.
Basidiomycota are filamentous fungi composed of hyphae (except for basidiomycota-yeast) and reproduce sexually via the formation of specialized club-shaped end cells called basidia that normally bear external meiospores (usually four). These specialized spores are called basidiospores. However, some Basidiomycota are obligate asexual reproducers. Basidiomycota that reproduce asexually (discussed below) can typically be recognized as members of this division by gross similarity to others, by the formation of a distinctive anatomical feature (the clamp connection), cell wall components, and definitively by phylogenetic molecular analysis of DNA sequence data.
Classification
A 2007 classification, adopted by a coalition of 67 mycologists recognized three subphyla (Pucciniomycotina, Ustilaginomycotina, Agaricomycotina) and two other class level taxa (Wallemiomycetes, Entorrhizomycetes) outside of these, among the Basidiomycota. As now classified, the subphyla join and also cut across various obsolete taxonomic groups (see below) previously commonly used to describe Basidiomycota. According to a 2008 estimate, Basidiomycota comprise three subphyla (including six unassigned classes) 16 classes, 52 orders, 177 families, 1,589 genera, and 31,515 species.
Wijayawardene et al. 2020 produced an update that recognized 19 classes (Agaricomycetes, Agaricostilbomycetes, Atractiellomycetes, Bartheletiomycetes, Classiculomycetes, Cryptomycocolacomycetes, Cystobasidiomycetes, Dacrymycetes, Exobasidiomycetes, Malassez |
https://en.wikipedia.org/wiki/Timeline%20of%20information%20theory | A timeline of events related to information theory, quantum information theory and statistical physics, data compression, error correcting codes and related subjects.
1872 – Ludwig Boltzmann presents his H-theorem, and with it the formula Σpi log pi for the entropy of a single gas particle
1878 – J. Willard Gibbs defines the Gibbs entropy: the probabilities in the entropy formula are now taken as probabilities of the state of the whole system
1924 – Harry Nyquist discusses quantifying "intelligence" and the speed at which it can be transmitted by a communication system
1927 – John von Neumann defines the von Neumann entropy, extending the Gibbs entropy to quantum mechanics
1928 – Ralph Hartley introduces Hartley information as the logarithm of the number of possible messages, with information being communicated when the receiver can distinguish one sequence of symbols from any other (regardless of any associated meaning)
1929 – Leó Szilárd analyses Maxwell's Demon, showing how a Szilard engine can sometimes transform information into the extraction of useful work
1940 – Alan Turing introduces the deciban as a measure of information inferred about the German Enigma machine cypher settings by the Banburismus process
1944 – Claude Shannon's theory of information is substantially complete
1947 – Richard W. Hamming invents Hamming codes for error detection and correction (to protect patent rights, the result is not published until 1950)
1948 – Claude E. Shannon publishes A Mathematical Theory of Communication
1949 – Claude E. Shannon publishes Communication in the Presence of Noise – Nyquist–Shannon sampling theorem and Shannon–Hartley law
1949 – Claude E. Shannon's Communication Theory of Secrecy Systems is declassified
1949 – Robert M. Fano publishes Transmission of Information. M.I.T. Press, Cambridge, Massachusetts – Shannon–Fano coding
1949 – Leon G. Kraft discovers Kraft's inequality, which shows the limits of prefix codes
1949 – |
https://en.wikipedia.org/wiki/Lempel%E2%80%93Ziv%E2%80%93Oberhumer | Lempel–Ziv–Oberhumer (LZO) is a lossless data compression algorithm that is focused on decompression speed.
Design
The original "lzop" implementation, released in 1996, was developed by Markus Franz Xaver Johannes Oberhumer, based on earlier algorithms by Abraham Lempel and Jacob Ziv. The LZO library implements a number of algorithms with the following characteristics:
Higher compression speed compared to DEFLATE compression
Very fast decompression
Requires an additional buffer during compression (of size 8 kB or 64 kB, depending on compression level)
Requires no additional memory for decompression other than the source and destination buffers
Allows the user to adjust the balance between compression ratio and compression speed, without affecting the speed of decompression
LZO supports overlapping compression and in-place decompression. As a block compression algorithm, it compresses and decompresses blocks of data. Block size must be the same for compression and decompression. LZO compresses a block of data into matches (a sliding dictionary) and runs of non-matching literals to produce good results on highly redundant data and deals acceptably with non-compressible data, only expanding incompressible data by a maximum of 1/64 of the original size when measured over a block size of at least 1 kB.
Implementations
The reference implementation is written in ANSI C, and it has been made available as free software under the GNU General Public License. The copyright for the code is owned by Markus F. X. J. Oberhumer. It was originally published in 1996. Oberhumer has also written a command-line frontend called lzop.
Versions of LZO are available for the Perl, Python and Java languages. Various LZO implementations are reported to work under Win32, AIX, ConvexOS, IRIX, Mac OS, Palm OS, PlayStation, Nintendo 64, Wii, Solaris, SunOS, TOS (Atari ST), Linux and VxWorks.
FFmpeg's libavutil library includes its own implementation of LZO as a possible method for lossl |
https://en.wikipedia.org/wiki/Science%20On%20a%20Sphere | Science On a Sphere (SOS) is a spherical projection system created by the United States National Oceanic and Atmospheric Administration (NOAA). It presents high-resolution video on a suspended globe rather than a flat screen, with the aim of better representing global phenomena. Animated images of atmospheric storms, climate change, and ocean temperature can be shown on the sphere to explain these complex environmental processes. SOS systems are most frequently installed in Science museums, universities, zoos, and research institutions.
History
SOS was invented by Alexander E. MacDonald, the former director of the Earth System Research Laboratory. MacDonald devised the original idea for SOS in 1995. A team of NOAA staff wrote the SOS software and developed the SOS hardware and system architecture. A patent was awarded to NOAA for Science On a Sphere in August 2005.
Configuration
SOS uses many off-the-shelf hardware and software components. A spherical screen covered in ordinary latex paint hangs suspended in the center of projection space. The screen is inert; it neither moves nor has any electronic parts. Surrounding the screen are four video projectors, with each projector responsible for one quadrant of screen space. One CPU is used to control the system. The SOS software runs on Linux.
The sphere
The carbon fiber sphere is in diameter. Other sphere sizes are possible. The 68" sphere with a single seam at the equator weighs under . The sphere is attached to the ceiling or suspension structure with a three-point suspension system to hold the sphere in place and reduce lateral movement and blurring.
Projectors
The system requires high quality, bright, long-duty cycle projectors, rather than smaller portable and consumer models to endure the requirements of 8–10 hours per day, 7 days per week of most public displays.
Computer hardware
The newest configuration uses one Ubuntu Linux computer with NVIDIA Quadro graphics cards, and an iPad app to control the syste |
https://en.wikipedia.org/wiki/The%20Michael%20J.%20Fox%20Foundation | The Michael J. Fox Foundation for Parkinson's Research aims to find a cure for Parkinson's disease (PD) founded in 2000 by Michael J. Fox. It concentrates on funding research and ensuring the development of improved therapies for people with Parkinson's.
History
Established in 2000 by Canadian actor Michael J. Fox, the foundation has since become the largest non-profit funder of Parkinson's disease research in the world, with more than $1 billion of research projects to date. In 2010, the Foundation launched the first large-scale clinical study on evolution biomarkers of the disease at a cost of $45 million over five years.
Research funding
The Foundation works towards "translational" research—the work of translating basic scientific discoveries into simple treatments with definition to benefit the estimated five million people living with Parkinson's disease today.
The Foundation drives progress by awarding grants to ensure that the most promising research avenues are thoroughly funded, explored and carried forward toward pharmacy shelves. The Foundation's four annually recurring Pipeline Programs aim to speed research along the drug development pipeline. The Pipeline Programs include:
Rapid Response Innovation Awards quickly support high-risk, high-reward projects with little to no existing preliminary data, but potential to significantly impact our understanding or treatment of PD (an Edmond J. Safra Core Program for PD Research).
Target Validation Awards provide support for work demonstrating whether modulation of a novel biological target has impact in a PD-relevant pre-clinical model — an essential step to the development of potential targeted therapies (an Edmond J. Safra Core Program for PD Research).
Clinical Intervention Awards support clinical testing of promising PD therapies that may significantly and fundamentally improve treatment of PD (an Edmond J. Safra Core Program for PD Research).
Therapeutics Development Initiative, an industry-exclus |
https://en.wikipedia.org/wiki/Paraphrasing%20%28computational%20linguistics%29 | Paraphrase or paraphrasing in computational linguistics is the natural language processing task of detecting and generating paraphrases. Applications of paraphrasing are varied including information retrieval, question answering, text summarization, and plagiarism detection. Paraphrasing is also useful in the evaluation of machine translation, as well as semantic parsing and generation of new samples to expand existing corpora.
Paraphrase generation
Multiple sequence alignment
Barzilay and Lee proposed a method to generate paraphrases through the usage of monolingual parallel corpora, namely news articles covering the same event on the same day. Training consists of using multi-sequence alignment to generate sentence-level paraphrases from an unannotated corpus. This is done by
finding recurring patterns in each individual corpus, i.e. " (injured/wounded) people, seriously" where are variables
finding pairings between such patterns the represent paraphrases, i.e. " (injured/wounded) people, seriously" and " were (wounded/hurt) by , among them were in serious condition"
This is achieved by first clustering similar sentences together using n-gram overlap. Recurring patterns are found within clusters by using multi-sequence alignment. Then the position of argument words is determined by finding areas of high variability within each cluster, aka between words shared by more than 50% of a cluster's sentences. Pairings between patterns are then found by comparing similar variable words between different corpora. Finally, new paraphrases can be generated by choosing a matching cluster for a source sentence, then substituting the source sentence's argument into any number of patterns in the cluster.
Phrase-based Machine Translation
Paraphrase can also be generated through the use of phrase-based translation as proposed by Bannard and Callison-Burch. The chief concept consists of aligning phrases in a pivot language to produce potential paraphrases in the origi |
https://en.wikipedia.org/wiki/Marine%20optical%20buoy | The marine optical buoy (MOBY) measures light at and very near the sea surface in a specific location over a long period of time, serving as part of an ocean color observation system. Satellites are another component of the system, providing global coverage through remote sensing; however, satellites measure light above the Earth's atmosphere, becoming subject to interference from the atmosphere itself and other light sources. The Marine Optical Buoy helps alleviate that interference and thus improve the quality of the overall ocean color observation system.
Physical description
MOBY is a buoy 15 meters tall floating vertically in the water with approximately 3 meters above the surface and 12 meters below. A float canister is at water level, measuring approximately 2 meters high and 1.5 meters in diameter above the water, 1 meter in diameter below the water. Above the float canister are four solar panels and an antenna column. From the bottom of the float canister, a central column descends to a 2-meter-high, 1-meter-diameter instrument canister. Along the central column are three standoff arms measuring 3 meters long, 2.5 meters long, and 2 meters long, respectively. The standoff arms can be relocated up and down the central column during maintenance. Light collectors are at the ends of the standoff arms and at the top of the antenna column. The antenna column includes Global Positioning System (GPS), very high frequency (VHF), and cellular telephone antennas. Computers, communications, and control electronics occupy the float canister. A marine optical system (MOS), a power system, and batteries occupy the instrument canister. The MOS includes spectrographs with charge-coupled device (CCD) detectors, an optical multiplexer, and fiber optic sensor lines to the light collectors.
MOBY has a tether to another buoy that is moored to the sea floor at a depth of about 1200 meters. MOBY is located at , west of Lanai, in the lee of the Hawaiian Islands.
Function
Light f |
https://en.wikipedia.org/wiki/PLOS%20Genetics | PLOS Genetics is a peer-reviewed open access scientific journal established in 2005 and published by the Public Library of Science. The founding editor-in-chief was Wayne N. Frankel (Columbia University Medical Center). The current editors-in-chief are Gregory S. Barsh (HudsonAlpha Institute of Biotechnology and Stanford University School of Medicine) and Gregory P. Copenhaver (The University of North Carolina at Chapel Hill). The journal covers research on all aspects of genetics and genomics.
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2020 impact factor of 5.917.
Research Prize
Since its tenth year of publication, the journal annually awards the $5000 PLOS Genetics Research Prize for the best paper published in the previous year based on nominations from members of the genetics community. |
https://en.wikipedia.org/wiki/Swarm%20Development%20Group | The Swarm Development Group (SDG) is an American non-profit organization to advance the development of complex adaptive system-oriented agent-based modeling (ABM) tools initiated at the Santa Fe Institute (SFI) in Santa Fe, New Mexico, US.
History
Swarm Development Group was formed in 1999 by a group of multidisciplinary scientists, researchers, and software developers, led by Chris Langton. Langton was also the founder of the emerging field of research called artificial life. The initial, primary, role for the SDG was to house continued development of the Swarm simulation software after the software become independent of the SFI in 1999.
The role of the Swarm Development Group has expanded to include the co-ordination of a long-running conference SwarmFest during May, June, or July each summer – typically hosted by a different research university each year. Developers, users, and researchers gather to present research papers and discuss the state of Swarm and other agent-based modeling platforms like RePast (University of Chicago) and Ascape (Brookings). Typically, a wide range of academic, corporate, and government organizations are represented at SwarmFest. The first SwarmFest was in 1998 while Swarm was still sponsored by the Santa Fe Institute. From SwarmFest 2000 onwards, after the SDG was formed in late 1999, SwarmFests were organized directly by the SDG.
Recent SwarmFests have been held at a variety of institutions. SwarmFest 2007 was held at DePaul University's School of Computer Science, Telecommunications, and Information Systems, in Chicago. SwarmFest 2008 was held at Northwestern Memorial Hospital/Northwestern University Feinberg School of Medicine, in Chicago. Swarmfest 2008 had special focus areas on agent based modeling in Systems Biology, and the implementation of agent based models in high-performance computing environments. Between 2009 and 2012, SwarmFest was held at the Santa Fe Complex in Santa Fe, New Mexico. Swarmfest 2013 was |
https://en.wikipedia.org/wiki/%C3%96mer%20Cerraho%C4%9Flu | Ömer Cerrahoğlu (born 3 May 1995) is a Romanian child prodigy in mathematics. At the age of , he won a gold medal at the 2009 International Mathematical Olympiad, making him the third-youngest gold medalist in IMO history, behind Terence Tao and Raúl Chávez Sarmiento.
Early life and education
He was born in Istanbul, Turkey to a Romanian mother and a Turkish father and when he was five years old, he moved with his family to Baia Mare, Romania. He graduated from the Massachusetts Institute of Technology (MIT) in June 2018, where he studied computer science.
Career
In 2017, he participated in the 78th William Lowell Putnam Mathematical Competition as a student of MIT and earned a Putnam Fellowship. Since his victory in 2009, he won three more silver medals at the 2010, 2011 and 2013 IMO's missing the gold by only 1, 2 and 1 points, respectively, and one more gold medal at the IMO 2012 in Argentina.
See also
List of child prodigies
List of International Mathematical Olympiad participants |
https://en.wikipedia.org/wiki/Routing%20Information%20Protocol | The Routing Information Protocol (RIP) is one of the oldest distance-vector routing protocols which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from source to destination. The largest number of hops allowed for RIP is 15, which limits the size of networks that RIP can support.
RIP implements the split horizon, route poisoning, and holddown mechanisms to prevent incorrect routing information from being propagated.
In RIPv1 routers broadcast updates with their routing table every 30 seconds. In the early deployments, routing tables were small enough that the traffic was not significant. As networks grew in size, however, it became evident there could be a massive traffic burst every 30 seconds, even if the routers had been initialized at random times.
In most networking environments, RIP is not the preferred choice of routing protocol, as its time to converge and scalability are poor compared to EIGRP, OSPF, or IS-IS. However, it is easy to configure, because RIP does not require any parameters, unlike other protocols.
RIP uses the User Datagram Protocol (UDP) as its transport protocol, and is assigned the reserved port number 520.
Development of distance-vector routing
Based on the Bellman–Ford algorithm and the Ford–Fulkerson algorithm, distance-vector routing protocols started to be implemented from 1969 onwards in data networks such as the ARPANET and CYCLADES. The predecessor of RIP was the Gateway Information Protocol (GWINFO) which was developed by Xerox in the mid-1970s to route its experimental network. As part of the Xerox Network Systems (XNS) protocol suite GWINFO transformed into the XNS Routing Information Protocol. This XNS RIP in turn became the basis for early routing protocols, such as Novell's IPX RIP, AppleTalk's Routing Table Maintenance Protocol (RTMP), and the IP RIP. The 1982 Berkley Software Distribution of the UNIX operating system implemented RIP i |
https://en.wikipedia.org/wiki/Cole%E2%80%93Hopf%20transformation | The Cole–Hopf transformation is a method of solving parabolic partial differential equations (PDEs) with a quadratic nonlinearity of the form:where , are constants, is the Laplace operator, is the gradient, and is the -norm. By assuming that , where is an unknown smooth function, we may calculate:Which implies that:if we constrain to satisfy . Then we may transform the original nonlinear PDE into the canonical heat equation by using the transformation:
This is the Cole-Hopf transformation. With the transformation, the following initial-value problem can now be solved:The unique, bounded solution of this system is:Since the Cole–Hopf transformation implies that , the solution of the original nonlinear PDE is:
Applications
Aerodynamics
Stochastic optimal control
Solving the viscous Burgers' equation |
https://en.wikipedia.org/wiki/Degree-preserving%20randomization | Degree Preserving Randomization is a technique used in Network Science that aims to assess whether or not variations observed in a given graph could simply be an artifact of the graph's inherent structural properties rather than properties unique to the nodes, in an observed network.
Background
Cataloged as early as 1996, the simplest implementation of degree preserving randomization relies on a Monte Carlo algorithm that rearranges, or "rewires" the network at random such that, with a sufficient number of rewires, the network's degree distribution is identical to the initial degree distribution of the network, though the topological structure of the network has become completely distinct from the original network.
Degree preserving randomization, while it has many different forms, typically takes on the form of a relatively simple approach: for any network consisting of nodes with edges, select two dyadically tied nodes. For each of these dyadic pairs, switch the edges such that the new dyadic pairs are mismatched. After a sufficient number of these mismatches, the network increasingly loses its original observed topography.
As is common with algorithms based on Markov chains, the number of iterations, or individual rewires, that must occur on a given graph such that the graph is sufficiently random and distinct from the original graph is unknown, though Espinoza asserts that a safe minimum threshold is , where "is at least 100" (Espinoza). Others have provided input for this issue, including one author who states that a safe minimum may instead be at least , where epsilon lies in a range between and , though ultimately the correct number is not presently known.
Uses
There are several cases in which published research have explicitly employed degree preserving randomization in order to analyze network properties. Dekker used rewiring in order to more accurately model observed social networks by adding a secondary variable, , which introduces a high-degree |
https://en.wikipedia.org/wiki/Tera%20100 | Tera 100 is a supercomputer built by Bull SA for the French Commissariat à l'Énergie Atomique.
On May 26, 2010, Tera 100 was turned on. The computer, which is located in Essonne is able to sustain around 1 petaFLOPs maximum performance and a peak at 1.25 petaFLOPs. It has 4300 Bullx Series S servers ('Mesca'), 140,000 Intel Xeon 7500 processor cores, and 300 TB of memory. The Interconnect is QDR InfiniBand. The file system has a throughput of 500 GB/s and total storage of 20 PB. It uses the SLURM resource manager for scheduling batch jobs.
Tera 100 uses Bull XBAS Linux, a partly Red Hat Enterprise Linux derivative.
In June 2011, TOP500 deemed it the ninth fastest supercomputer in the world, and in 2020, it had dropped off the list.
See also
Computer science
Computing
Tera-10 |
https://en.wikipedia.org/wiki/Willmore%20conjecture | In differential geometry, the Willmore conjecture is a lower bound on the Willmore energy of a torus. It is named after the English mathematician Tom Willmore, who conjectured it in 1965. A proof by Fernando Codá Marques and André Neves was announced in 2012 and published in 2014.
Willmore energy
Let v : M → R3 be a smooth immersion of a compact, orientable surface. Giving M the Riemannian metric induced by v, let H : M → R be the mean curvature (the arithmetic mean of the principal curvatures κ1 and κ2 at each point). In this notation, the Willmore energy W(M) of M is given by
It is not hard to prove that the Willmore energy satisfies W(M) ≥ 4π, with equality if and only if M is an embedded round sphere.
Statement
Calculation of W(M) for a few examples suggests that there should be a better bound than W(M) ≥ 4π for surfaces with genus g(M) > 0. In particular, calculation of W(M) for tori with various symmetries led Willmore to propose in 1965 the following conjecture, which now bears his name
For every smooth immersed torus M in R3, W(M) ≥ 2π2.
In 1982, Peter Wai-Kwong Li and Shing-Tung Yau proved the conjecture in the non-embedded case, showing that if is an immersion of a compact surface, which is not an embedding, then W(M) is at least 8π.
In 2012, Fernando Codá Marques and André Neves proved the conjecture in the embedded case, using the Almgren–Pitts min-max theory of minimal surfaces. Martin Schmidt claimed a proof in 2002, but it was not accepted for publication in any peer-reviewed mathematical journal (although it did not contain a proof of the Willmore conjecture, he proved some other important conjectures in it). Prior to the proof of Marques and Neves, the Willmore conjecture had already been proved for many special cases, such as tube tori (by Willmore himself), and for tori of revolution (by Langer & Singer). |
https://en.wikipedia.org/wiki/73%20%28number%29 | 73 (seventy-three) is the natural number following 72 and preceding 74. In English, it is the smallest natural number with twelve letters in its spelled out name.
In mathematics
73 is the 21st prime number, and emirp with 37, the 12th prime number. It is also the eighth twin prime, with 71. It is the largest minimal primitive root in the first 100,000 primes; in other words, if is one of the first one hundred thousand primes, then at least one of the numbers 2, 3, 4, 5, 6, ..., 73 is a primitive root modulo . 73 is also the smallest factor of the first composite generalized Fermat number in decimal: , and the smallest prime congruent to 1 modulo 24, as well as the only prime repunit in octal (1118). It is the fourth star number.
Sheldon prime
Notably, 73 is the only Sheldon prime to contain both "mirror" and "product" properties:
73, as an emirp, has 37 as its dual permutable prime, a mirroring of its base ten digits, 7 and 3. 73 is the 21st prime number, while 37 is the 12th, which is a second mirroring; and
73 has a prime index of 21 = 7 × 3; a product property where the product of its base-10 digits is precisely its index in the sequence of prime numbers.
Arithmetically, from sums of 73 and 37 with their prime indexes, one obtains:
Meanwhile,
In binary 73 is represented as , while 21 in binary is , with 7 and 3 represented as and respectively; all which are palindromic. Of the seven binary digits representing 73, there are three 1s. In addition to having prime factors 7 and 3, the number represents the ternary (base-3) equivalent of the decimal numeral 7, that is to say: .
Other properties
The row sum of Lah numbers of the form with and is equal to . These numbers represent coefficients expressing rising factorials in terms of falling factorials, and vice-versa; equivalently in this case to the number of partitions of into any number of lists, where a list means an ordered subset.
73 requires 115 steps to return to 1 in the Collatz problem, |
https://en.wikipedia.org/wiki/Help%20%28command%29 | In computing, help is a command in various command line shells such as COMMAND.COM, cmd.exe, Bash, qshell, 4DOS/4NT, Windows PowerShell, Singularity shell, Python, MATLAB and GNU Octave. It provides online information about available commands and the shell environment.
Implementations
The command is available in operating systems such as Multics, Heath Company HDOS, CP/M Plus, DOS, IBM OS/2, eComStation, ArcaOS, IBM i, Microsoft Windows, ReactOS, THEOS/OASIS, Zilog Z80-RIO, Microware OS-9, Stratus OpenVOS, HP MPE/iX, Motorola VERSAdos, KolibriOS and also in the DEC RT-11, RSX-11, TOPS-10 and TOPS-20 operating systems. Furthermore it is available in the open source MS-DOS emulator DOSBox and in the EFI shell.
On Unix, the command is part of the Source Code Control System and prints help information for the SCCS commands.
Multics
The Multics help command prints descriptions of system commands/active functions and subroutines. It also prints various information about the system status, system changes, and other general information. This information is selected from segments maintained online, which are in a special format, called information segments. More than 800 information segments are available.
DEC OS/8
The DEC OS/8 CCL help command prints information on specified OS/8 programs.
DOS
MS-DOS
The help command is available in MS-DOS 5.x and later versions of the software.
The help command with a 'command' parameter would give help on a specific command.
If no arguments are provided, the command lists the contents of DOSHELP.HLP.
In MS-DOS 6.x this command exists as FASTHELP.
The MS-DOS 6.xx help command uses QBasic to view a quickhelp HELP.HLP file, which contains more extensive information on the commands, with some hyperlinking etc. The MS-DOS 6.22 help system is included on Windows 9x CD-ROM versions as well.
PC DOS
In PC DOS 5 and 6 help is the same form as MS-DOS 5 help command.
PC DOS 7.xx help uses view.exe to open OS/2 style INF files (cmdref.inf, |
https://en.wikipedia.org/wiki/Sander%20P.%20Zwegers | Sander Pieter Zwegers (born April 16, 1975) is a Dutch mathematician who made a connection between Maass forms and Srinivasa Ramanujan's mock theta functions in 2002. He was born in Oosterhout. After a period at the Max-Planck Institute in Bonn, he became an assistant professor at the University College Dublin in 2008. Since 2011, he has been is professor of number theory at the University of Cologne.
Research
In 1976, the American mathematician George Andrews found what is nowadays known as the "Lost Notebook" of Ramanujan. It contains many remarkable results, including the mysterious mock theta functions.
This notebook contains what many specialists regard as Ramanujan’s deepest work. It was Sander Zwegers who, as a PdD student, had groundbreaking ideas how to fit the mock theta functions into a broader context. His 2002 PhD thesis has led to numerous publications and international conferences.
Zwegers' general area of interest is number theory. More specifically, he studies modular forms and variations thereof, such as Maass forms, mock modular forms, (indefinite) theta functions, and (Maass) Jacobi forms.
Works |
https://en.wikipedia.org/wiki/Space-time%20adaptive%20processing | Space-time adaptive processing (STAP) is a signal processing technique most commonly used in radar systems. It involves adaptive array processing algorithms to aid in target detection. Radar signal processing benefits from STAP in areas where interference is a problem (i.e. ground clutter, jamming, etc.). Through careful application of STAP, it is possible to achieve order-of-magnitude sensitivity improvements in target detection.
STAP involves a two-dimensional filtering technique using a phased-array antenna with multiple spatial channels. Coupling multiple spatial channels with pulse-Doppler waveforms lends to the name "space-time." Applying the statistics of the interference environment, an adaptive STAP weight vector is formed. This weight vector is applied to the coherent samples received by the radar.
History
The theory of STAP was first published by Lawrence E. Brennan and Irving S. Reed in the early 1970s. At the time of publication, both Brennan and Reed were at Technology Service Corporation (TSC). While it was formally introduced in 1973, it has theoretical roots dating back to 1959.
Motivation and applications
For ground-based radar, cluttered returns tend to be at DC, making them easily discriminated by Moving Target Indication (MTI). Thus, a notch filter at the zero-Doppler bin can be used. Airborne platforms with ownship motion experience relative ground clutter motion dependent on the angle, resulting in angle-Doppler coupling at the input. In this case, 1D filtering is not sufficient, since clutter can overlap the desired target's Doppler from multiple directions. The resulting interference is typically called a "clutter ridge," since it forms a line in the angle-Doppler domain. Narrowband jamming signals are also a source of interference, and exhibit significant spatial correlation. Thus receiver noise and interference must be considered, and detection processors must attempt to maximize the signal-to-interference and noise ratio (SINR). |
https://en.wikipedia.org/wiki/Geographic%20routing | Geographic routing (also called georouting or position-based routing) is a routing principle that relies on geographic position information. It is mainly proposed for wireless networks and based on the idea that the source sends a message to the geographic location of the destination instead of using the network address. In the area of packet radio networks, the idea of using position information for routing was first proposed in the 1980s for interconnection networks. Geographic routing requires that each node can determine its own location and that the source is aware of the location of the destination. With this information, a message can be routed to the destination without knowledge of the network topology or a prior route discovery.
Approaches
There are various approaches, such as single-path, multi-path and flooding-based strategies (see for a survey). Most single-path strategies rely on two techniques: greedy forwarding and face routing. Greedy forwarding tries to bring the message closer to the destination in each step using only local information. Thus, each node forwards the message to the neighbor that is most suitable from a local point of view. The most suitable neighbor can be the one who minimizes the distance to the destination in each step (Greedy). Alternatively, one can consider another notion of progress, namely the projected distance on the source-destination-line (MFR, NFP), or the minimum angle between neighbor and destination (Compass Routing). Not all of these strategies are loop-free, i.e. a message can circulate among nodes in a certain constellation. It is known that the basic greedy strategy and MFR are loop free, while NFP and Compass Routing are not.
Greedy forwarding can lead into a dead end, where there is no neighbor closer to the destination. Then, face routing helps to recover from that situation and find a path to another node, where greedy forwarding can be resumed. A recovery strategy such as face routing is necessary to ass |
https://en.wikipedia.org/wiki/Ramification%20group | In number theory, more specifically in local class field theory, the ramification groups are a filtration of the Galois group of a local field extension, which gives detailed information on the ramification phenomena of the extension.
Ramification theory of valuations
In mathematics, the ramification theory of valuations studies the set of extensions of a valuation v of a field K to an extension L of K. It is a generalization of the ramification theory of Dedekind domains.
The structure of the set of extensions is known better when L/K is Galois.
Decomposition group and inertia group
Let (K, v) be a valued field and let L be a finite Galois extension of K. Let Sv be the set of equivalence classes of extensions of v to L and let G be the Galois group of L over K. Then G acts on Sv by σ[w] = [w ∘ σ] (i.e. w is a representative of the equivalence class [w] ∈ Sv and [w] is sent to the equivalence class of the composition of w with the automorphism ; this is independent of the choice of w in [w]). In fact, this action is transitive.
Given a fixed extension w of v to L, the decomposition group of w is the stabilizer subgroup Gw of [w], i.e. it is the subgroup of G consisting of all elements that fix the equivalence class [w] ∈ Sv.
Let mw denote the maximal ideal of w inside the valuation ring Rw of w. The inertia group of w is the subgroup Iw of Gw consisting of elements σ such that σx ≡ x (mod mw) for all x in Rw. In other words, Iw consists of the elements of the decomposition group that act trivially on the residue field of w. It is a normal subgroup of Gw.
The reduced ramification index e(w/v) is independent of w and is denoted e(v). Similarly, the relative degree f(w/v) is also independent of w and is denoted f(v).
Ramification groups in lower numbering
Ramification groups are a refinement of the Galois group of a finite Galois extension of local fields. We shall write for the valuation, the ring of integers and its maximal ideal for . As a consequence o |
https://en.wikipedia.org/wiki/List%20of%20sovereign%20states%20by%20date%20of%20current%20flag%20adoption | This is a list of sovereign states by the date in which they adopted their current national flag.
For most of these states, the date of flag adoption is clear, but for others the exact date of flag adoption is unknown or disputed because of design changes. This list defines the year of flag adoption as the year since when the current flag has been used continuously to represent a nation, autonomous region or occupied state. Only countries which are currently sovereign states are listed, although the flag may have been adopted before the countries gained independence. The listed countries may have undergone fundamental regime changes, great geographical changes or even temporarily lost autonomy, or undergone political unions or secessions. If the flag remained in use during such events, its original adoption date is listed. Changes that do not alter the basic design of the flag, like the changes in ratio or colour shade, restyling of emblems or inscriptions or the addition or removal of stars, are listed in the last column. The current flag design often evolved over the years (e.g. the flag of the United States) or can be a re-adoption of an earlier, historic flag (e.g. the flag of Libya). The year the current flag design first came into use is listed in the third column.
List
See also
Timeline of national flags
Notes |
https://en.wikipedia.org/wiki/Timeworks%20Publisher | Timeworks Publisher was a desktop publishing (DTP) program produced by GST Software in the United Kingdom.
It is notable as the first affordable DTP program for the IBM PC. In appearance and operation, it was a Ventura Publisher clone, but it was possible to run it on a computer without a hard disk.
Versions
Timeworks Desktop Publisher
Timeworks Publisher 1 for Atari TOS relied on the GDOS software components, which were available from Atari but were often distributed with applications that required them. GDOS provided TOS/GEM with a standardized method for installing printer drivers and additional fonts, although these were limited to bitmapped fonts in all but the later releases. GDOS had a reputation for being difficult to configure, used a lot of system resources and was fairly buggy, meaning that Timeworks could struggle to run on systems without a hard disk and less than 2 MB of memory - but it was possible, and for many users Timeworks was an inexpensive introduction to desktop publishing.
For the IBM PC, Timeworks ran on Digital Research's GEM Desktop (supplied with the program) as a runtime system. Later versions ran on Microsoft Windows.
Timeworks Publisher 2 included full WYSIWYG, paragraph tagging, manual control of kerning, text and graphics imports and more fonts. Timeworks Publisher 2.1 with GEM/5 is known to have supported Bézier curves already.
Acorn Desktop Publisher
In mid-1988, following on from the release of GST's word processor, First Word Plus, Acorn Computers announced that it had commissioned GST to port and enhance the Timeworks product for the Archimedes series. Being designed for use with RISC OS, using the anti-aliased font technology already demonstrated on the Archimedes, utilising the multi-tasking capabilities of the RISC OS desktop environment, and offering printed output support for laser and dot-matrix printers, availability was deferred until the release of RISC OS in April 1989. The delivered product, Acorn Desktop Publi |
https://en.wikipedia.org/wiki/Bee%20learning%20and%20communication | Bee learning and communication includes cognitive and sensory processes in all kinds of bees, that is the insects in the seven families making up the clade Anthophila. Some species have been studied more extensively than others, in particular Apis mellifera, or European honey bee. Color learning has also been studied in bumblebees.
Honey bees are sensitive to odors (including pheromones), tastes, and colors, including ultraviolet. They can demonstrate capabilities such as color discrimination through classical and operant conditioning and retain this information for several days at least; they communicate the location and nature of sources of food; they adjust their foraging to the times at which food is available; they may even form cognitive maps of their surroundings. They also communicate with each other by means of a "waggle dance" and in other ways.
Learning
Honey bees are adept at associative learning, and many of the phenomena of operant and classical conditioning take the same form in honey bees as they do in the vertebrates. Efficient foraging requires such learning. For example, honey bees make few repeat visits to a plant if it provides little in the way of reward. A single forager will visit different flowers in the morning and, if there is sufficient reward in a particular kind of flower, she will make visits to that type of flower for most of the day, unless the plants stop producing nectar or weather conditions change.
Memory
A 2005 three-part study tested the working memory of honey bees, after learning to associate a certain pattern with a reward (delayed matching-to-sample). Bees were shown a pattern at the beginning of a tunnel, and then subjected to a series of variations: in the length of the tunnel (How long can bees retain the pattern in working memory?), in a choice between two patterns (matching and non-matching) placed at different distances (Can bees trained in the task continue to perform correctly when the matching pattern as well |
https://en.wikipedia.org/wiki/Fundamental%20theorem%20of%20algebra | The fundamental theorem of algebra, also known as d'Alembert's theorem, or the d'Alembert–Gauss theorem, states that every non-constant single-variable polynomial with complex coefficients has at least one complex root. This includes polynomials with real coefficients, since every real number is a complex number with its imaginary part equal to zero.
Equivalently (by definition), the theorem states that the field of complex numbers is algebraically closed.
The theorem is also stated as follows: every non-zero, single-variable, degree n polynomial with complex coefficients has, counted with multiplicity, exactly n complex roots. The equivalence of the two statements can be proven through the use of successive polynomial division.
Despite its name, there is no purely algebraic proof of the theorem, since any proof must use some form of the analytic completeness of the real numbers, which is not an algebraic concept. Additionally, it is not fundamental for modern algebra; its name was given at a time when algebra was synonymous with theory of equations.
History
Peter Roth, in his book Arithmetica Philosophica (published in 1608, at Nürnberg, by Johann Lantzenberger), wrote that a polynomial equation of degree n (with real coefficients) may have n solutions. Albert Girard, in his book L'invention nouvelle en l'Algèbre (published in 1629), asserted that a polynomial equation of degree n has n solutions, but he did not state that they had to be real numbers. Furthermore, he added that his assertion holds "unless the equation is incomplete", by which he meant that no coefficient is equal to 0. However, when he explains in detail what he means, it is clear that he actually believes that his assertion is always true; for instance, he shows that the equation although incomplete, has four solutions (counting multiplicities): 1 (twice), and
As will be mentioned again below, it follows from the fundamental theorem of algebra that every non-constant polynomial with real c |
https://en.wikipedia.org/wiki/Hsiang%E2%80%93Lawson%27s%20conjecture | In mathematics, Lawson's conjecture states that the Clifford torus is the only minimally embedded torus in the 3-sphere S3. The conjecture was featured by the Australian Mathematical Society Gazette as part of the Millennium Problems series.
In March 2012, Simon Brendle gave a proof of this conjecture, based on maximum principle techniques. |
https://en.wikipedia.org/wiki/Monorepo | In version-control systems, a monorepo ("mono" meaning 'single' and "repo" being short for 'repository') is a software-development strategy in which the code for a number of projects is stored in the same repository. This practice dates back to at least the early 2000s, when it was commonly called a shared codebase. Google, Meta, Microsoft, Uber, Airbnb, and Twitter all employ very large monorepos with varying strategies to scale build systems and version control software with a large volume of code and daily changes.
A related concept is the monolithic application, but whereas a monolith combines its sub-projects into one large project, a monorepo may contain multiple independent projects.
Advantages
There are a number of potential advantages to a monorepo over individual repositories:
Ease of code reuse
Similar functionality or communication protocols can be abstracted into shared libraries and directly included by projects, without the need of a dependency package manager.
Simplified dependency management
In a multiple repository environment where multiple projects depend on a third-party dependency, that dependency might be downloaded or built multiple times. In a monorepo the build can be easily optimized, as referenced dependencies all exist in the same codebase.
Atomic commits
When projects that work together are contained in separate repositories, releases need to sync which versions of one project work with the other. And in large enough projects, managing compatible versions between dependencies can become dependency hell. In a monorepo this problem can be negated, since developers may change multiple projects atomically.
Large-scale code refactoring
Since developers have access to the entire project, refactors can ensure that every piece of the project continues to function after a refactor.
Collaboration across teams
In a monorepo that uses source dependencies (dependencies that are compiled from source), teams can improve projects being w |
https://en.wikipedia.org/wiki/Gelfand%20pair | In mathematics, a Gelfand pair is a pair (G,K) consisting of a group G and a subgroup K (called an Euler subgroup of G) that satisfies a certain property on restricted representations. The theory of Gelfand pairs is closely related to the topic of spherical functions in the classical theory of special functions, and to the theory of Riemannian symmetric spaces in differential geometry. Broadly speaking, the theory exists to abstract from these theories their content in terms of harmonic analysis and representation theory.
When G is a finite group the simplest definition is, roughly speaking, that the (K,K)-double cosets in G commute. More precisely, the Hecke algebra, the algebra of functions on G that are invariant under translation on either side by K, should be commutative for the convolution on G.
In general, the definition of Gelfand pair is roughly that the restriction to K of any irreducible representation of G contains the trivial representation of K with multiplicity no more than 1. In each case one should specify the class of considered representations and the meaning of contains.
Definitions
In each area, the class of representations and the definition of containment for representations is slightly different. Explicit definitions in several such cases are given here.
Finite group case
When G is a finite group the following are equivalent
(G,K) is a Gelfand pair.
The algebra of (K,K)-double invariant functions on G with multiplication defined by convolution is commutative.
For any irreducible representation π of G, the space πK of K-invariant vectors in π is no-more-than-1-dimensional.
For any irreducible representation π of G, the dimension of HomK(π, C) is less than or equal to 1, where C denotes the trivial representation.
The permutation representation of G on the cosets of K is multiplicity-free, that is, it decomposes into a direct sum of distinct absolutely irreducible representations in characteristic zero.
The centralizer algebra (Schur |
https://en.wikipedia.org/wiki/VM%20%28operating%20system%29 | VM (often: VM/CMS) is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers.
The following versions are known:
Virtual Machine Facility/370
VM/370, released in 1972, is a System/370 reimplementation of earlier CP/CMS operating system.
VM/370 Basic System Extensions Program Product
VM/BSE (BSEPP) is an enhancement to VM/370 that adds support for more devices (such as 3370-type fixed-block-architecture DASD drives), improvements to the CMS environment (such as an improved editor), and some stability enhancements to CP.
VM/370 System Extensions Program Product
VM/SE (SEPP) is an enhancement to VM/370 that includes the facilities of VM/BSE, as well as a few additional fixes and features.
Virtual Machine/System Product
VM/SP, a milestone version, replaces VM/370, VM/BSE and VM/SE. Release 1 added EXEC2 and XEDIT System Product Editor; Release 3 added REXX; Release 6 added the shared filesystem.
Virtual Machine/System Product High Performance Option
VM/SP HPO adds additional device support and functionality to VM/SP, and allows certain S/370 machines that can utilize more than 16 MB of real storage to do so, up to 64 MB. This version was intended for users that would be running multiple S/370 guests at once.
Virtual Machine/Extended Architecture Migration Aid
VM/XA MA is intended to ease the migration from MVS/370 to MVS/XA by allowing both to run concurrently on the same processor complex.
Virtual Machine/Extended Architecture System Facility
VM/XA SF is an upgraded VM/XA MA with improved functionality and performance.
Virtual Machine/Extended Architecture System Product
VM/XA SP is an upgraded VM/XA MA with improved functionality and performance, offered as a replacement for VM/SP HPO on machines supporting S/370-XA. It includes a version of CMS that can run in either S/370 or S/370-XA mode.
Virtual Machine/Enterprise |
https://en.wikipedia.org/wiki/Hartree%20equation | In 1927, a year after the publication of the Schrödinger equation, Hartree formulated what are now known as
the Hartree equations for atoms, using the concept of self-consistency that Lindsay had introduced in his study of many electron systems in the context of Bohr theory. Hartree assumed that the nucleus together with the electrons formed a spherically symmetric field. The charge distribution of each electron was the solution of the Schrödinger equation for an electron in a potential , derived from the field. Self-consistency required that the final field, computed from the solutions, was self-consistent with the initial field, and he thus called his method the self-consistent field method.
History
In order to solve the equation of an electron in a spherical potential, Hartree first introduced atomic units to eliminate physical constants. Then he converted the Laplacian from Cartesian to spherical coordinates to show that the solution was a product of a radial function and a spherical harmonic with an angular quantum number , namely . The equation for the radial function was
Hartree equation in mathematics
In mathematics, the Hartree equation, named after Douglas Hartree, is
in
where
and
The non-linear Schrödinger equation is in some sense a limiting case.
Hartree product
The wavefunction which describes all of the electrons, , is almost always too complex to calculate directly. Hartree's original method was to first calculate the solutions to Schrödinger's equation for individual electrons 1, 2, 3, , p, in the states , which yields individual solutions: . Since each is a solution to the Schrödinger equation by itself, their product should at least approximate a solution. This simple method of combining the wavefunctions of the individual electrons is known as the Hartree product:
This Hartree product gives us the wavefunction of a system (many-particle) as a combination of wavefunctions of the individual particles. It is inherently mean-fie |
https://en.wikipedia.org/wiki/Manot%20Cave | Manot Cave ( Me'arat Manot) is a cave in Western Galilee, Israel, discovered in 2008. It is notable for the discovery of a skull that belongs to a modern human, called Manot 1, which is estimated to be 54,700 years old (U–Th dating of the calcitic crust on the Manot 1 calvaria and of speleothems in the cave). The partial skull was discovered at the beginning of the cave's exploration in 2008. Its significance was realised after detailed scientific analysis, and was first published in an online edition of Nature on 28 January 2015. This age implies that the specimen is the oldest known human outside Africa, and is evidence that modern humans lived side-by-side with Neanderthals. The cave is also noted for its "impressive archaeological record of flint and bone artefacts". Geologically, it is an "active stalactite cave".
Discovery
Manot Cave is situated in Western Galilee, about 10 km north of HaYonim Cave and 50 km northeast of Mt. Carmel. It was discovered accidentally during a construction work in 2008 when a bulldozer struck open its roof. Experts from the Cave Research Unit of Hebrew University of Jerusalem immediately made the initial survey. Important finds were stone tools, charcoal pieces, and human remains. The tools consisted of a Levallois point, burins, bladelets, overpassed blades, and Aurignacian tools such as nosed and carinated endscrapers. There were also remains of "fallow deer, red deer, mountain gazelle, horse, aurochs, hyena, and bear". The major find was an almost complete human skull. The finds were reported to the Israel Antiquities Authority (IAA), which granted another survey. Ofer Marder and H. Khalaily made the survey and found that it was a rich archaeological site. Recognising its importance, the IAA granted a full-scale excavation in 2010. For three weeks the site was excavated by a collaboration of archaeologists from Hebrew University of Jerusalem, Tel Aviv University, Geological Survey of Israel, Zinman Institute of Archaeology of |
https://en.wikipedia.org/wiki/David%20Richardson%20Medal | The David Richardson Medal is awarded by the Optical Society (formerly the Optical Society of America) to recognize contributions to optical engineering, primarily in the commercial and industrial sector. The award was first made in 1966 to its namesake David J. Richardson. He received it for distinctive contributions to the ruling and replicating of gratings, used to determine the transfer functions of lenses. There is a prize associated with the medal.
Richardson received a graduate degree in spectroscopy from the Massachusetts Institute of Technology in the mid-1930s. He was hired by Bausch and Lomb in 1947 to establish a grating and scale-ruling laboratory that became the world's leader in diffraction gratings. The lab, which was renamed for him in 1966, has since 2004 belonged to the Newport Corporation.
Recipients
See also
List of physics awards |
https://en.wikipedia.org/wiki/Dirichlet%20character | In analytic number theory and related branches of mathematics, a complex-valued arithmetic function is a Dirichlet character of modulus (where is a positive integer) if for all integers and :
that is, is completely multiplicative.
(gcd is the greatest common divisor)
; that is, is periodic with period .
The simplest possible character, called the principal character, usually denoted , (see Notation below) exists for all moduli:
The German mathematician Peter Gustav Lejeune Dirichlet—for whom the character is named—introduced these functions in his 1837 paper on primes in arithmetic progressions.
Notation
is Euler's totient function.
is a complex primitive n-th root of unity:
but
is the group of units mod . It has order
is the group of Dirichlet characters mod .
etc. are prime numbers.
is a standard abbreviation for
etc. are Dirichlet characters. (the lowercase Greek letter chi for character)
There is no standard notation for Dirichlet characters that includes the modulus. In many contexts (such as in the proof of Dirichlet's theorem) the modulus is fixed. In other contexts, such as this article, characters of different moduli appear. Where appropriate this article employs a variation of Conrey labeling (introduced by Brian Conrey and used by the LMFDB).
In this labeling characters for modulus are denoted where the index is described in the section the group of characters below. In this labeling, denotes an unspecified character and
denotes the principal character mod .
Relation to group characters
The word "character" is used several ways in mathematics. In this section it refers to a homomorphism from a group (written multiplicatively) to the multiplicative group of the field of complex numbers:
The set of characters is denoted If the product of two characters is defined by pointwise multiplication the identity by the trivial character and the inverse by complex inversion then becomes an abelian group.
If is a |
https://en.wikipedia.org/wiki/Titan2d-mod | Titan2d-mod (titan 3.1.1, 2016) is a free open source code to simulate dry granular avalanche flows over natural terrain, modified from an early version (titan 3.0.0, 2011) of TITAN2D code. It is available in the contributor's home page http://lsec.cc.ac.cn/~lyuan/code.html, or searchable in the Sourceforge website.
Overview
The code allows for several variants of the shallow granular flow model, and the governing equations are discretized on Cartesian meshes and solved with the Davis predictor-corrector Godunov type method. The code structures and usage are the same as earlier TITAN2D versions (see user's manual ), but some bugs and errors occurring in titan 3.0.0 are corrected, and stopping criteria are added.
A non-hydrostatic Savage-Hutter model is implemented as the default.
See also
TITAN2D (open source geoflow simulation software) |
https://en.wikipedia.org/wiki/Comparison%20of%20open-source%20and%20closed-source%20software | Free/open-source software – the source availability model used by free and open-source software (FOSS) – and closed source are two approaches to the distribution of software.
Background
Under the closed-source model source code is not released to the public. Closed-source software is maintained by a team who produces their product in a compiled-executable state, which is what the market is allowed access to. Microsoft, the owner and developer of Windows and Microsoft Office, along with other major software companies, have long been proponents of this business model, although in August 2010, Microsoft interoperability general manager Jean Paoli said Microsoft "loves open source" and its anti-open-source position was a mistake.
The FOSS model allows for able users to view and modify a product's source code, but most of such code is not in the public domain. Common advantages cited by proponents for having such a structure are expressed in terms of trust, acceptance, teamwork and quality.
A non-free license is used to limit what free software movement advocates consider to be the essential freedoms. A license, whether providing open-source code or not, that does not stipulate the "four software freedoms", are not considered "free" by the free software movement. A closed source license is one that limits only the availability of the source code. By contrast a copyleft license claims to protect the "four software freedoms" by explicitly granting them and then explicitly prohibiting anyone to redistribute the package or reuse the code in it to make derivative works without including the same licensing clauses. Some licenses grant the four software freedoms but allow redistributors to remove them if they wish. Such licenses are sometimes called permissive software licenses. An example of such a license is the FreeBSD License which allows derivative software to be distributed as non-free or closed source, as long as they give credit to the original designers.
A miscon |
https://en.wikipedia.org/wiki/Arithmetico-geometric%20sequence | In mathematics, arithmetico-geometric sequence is the result of term-by-term multiplication of a geometric progression with the corresponding terms of an arithmetic progression. Put plainly, the nth term of an arithmetico-geometric sequence is the product of the nth term of an arithmetic sequence
and the nth term of a geometric one. Arithmetico-geometric sequences arise in various applications, such as the computation of expected values in probability theory. For instance, the sequence
is an arithmetico-geometric sequence. The arithmetic component appears in the numerator (in blue), and the geometric one in the denominator (in green).
The summation of this infinite sequence is known as an arithmetico-geometric series, and its most basic form has been called Gabriel's staircase:
The denomination may also be applied to different objects presenting characteristics of both arithmetic and geometric sequences; for instance the French notion of arithmetico-geometric sequence refers to sequences of the form , which generalise both arithmetic and geometric sequences. Such sequences are a special case of linear difference equations.
Terms of the sequence
The first few terms of an arithmetico-geometric sequence composed of an arithmetic progression (in blue) with difference and initial value and a geometric progression (in green) with initial value and common ratio
are given by:
Example
For instance, the sequence
is defined by , , and .
Sum of the terms
The sum of the first terms of an arithmetico-geometric sequence has the form
where and are the th terms of the arithmetic and the geometric sequence, respectively.
This sum has the closed-form expression
Proof
Multiplying,
by , gives
Subtracting from , and using the technique of telescoping series gives
where the last equality results of the expression for the sum of a geometric series. Finally dividing through by gives the result.
Infinite series
If −1 < r < 1, then the sum S of the arithmetico-geome |
https://en.wikipedia.org/wiki/RadioVIS | RadioVIS is a protocol for sideband signalling of images and text messages for a broadcast audio service to provide a richer visual experience.
It is an application and sub-project of RadioDNS, which allows radio consumption devices to look up an IP-based service based on the parameters of the currently tuned broadcast station.
In January 2015, the functionality of RadioVIS was integrated to Visual Slideshow (ETSI TS 101 499 v3.1.1). The original RVIS01 document is now deprecated.
Details
The protocol enables either Streaming Text Oriented Messaging Protocol (STOMP) or Comet to deliver text and image URLs to a client, with the images being acquired over a HTTP connection.
The technology is currently implemented by a number of broadcasters across the world, including Global Radio, Bauer Radio in the UK, RTÉ in the Republic Of Ireland, Südwestrundfunk in Germany and a number of Australian media groups amongst others.
A number of software clients exist to show the protocol, as well as hardware devices such as the Pure Sensia from Pure Digital, and the Colourstream from Roberts Radio. |
https://en.wikipedia.org/wiki/Glial%20cell%20line-derived%20neurotrophic%20factor | Glial cell line-derived neurotrophic factor (GDNF) is a protein that, in humans, is encoded by the GDNF gene. GDNF is a small protein that potently promotes the survival of many types of neurons. It signals through GFRα receptors, particularly GFRα1.
It is also responsible for the determination of spermatogonia into primary spermatocytes, i.e. it is received by RET proto-oncogene (RET) and by forming gradient with SCF it divides the spermatogonia into two cells. As the result there is retention of spermatogonia and formation of spermatocyte.
GDNF family of ligands (GFL)
GDNF was discovered in 1991, and is the first member of the GDNF family of ligands (GFL) found.
Function
GDNF is highly distributed throughout both the peripheral and central nervous system. It can be secreted by astrocytes, oligodendrocytes, Schwann cells, motor neurons, and skeletal muscle during the development and growth of neurons and other peripheral cells.
The GDNF gene encodes a highly conserved neurotrophic factor. The recombinant form of this protein was shown to promote the survival and differentiation of dopaminergic neurons in culture, and was able to prevent apoptosis of motor neurons induced by axotomy. GDNF is synthesized as a 211 amino acid-long protein precursor, pro-GDNF. The pre-sequence leads the protein to the endoplasmic reticulum for secretion. While secretion takes place, the protein precursor folds via a sulfide-sulfide bond and dimerizes. The protein then is modified by N-linked glycosylation during packaging and preparation in the Golgi apparatus. Finally, the protein precursor undergoes proteolysis due to a proteolytic consensus sequence in its C-terminus end and is cleaved to 134 amino acids. Proteases that play a role in the proteolysis of pro-GDNF into mature GDNF include furin, PACE4, PC5A, PC5B, and PC7. Because multiple proteases can cleave the protein precursor, four different mature forms of GDNF can be produced. The proteolytic processing of GDNF requires Sor |
https://en.wikipedia.org/wiki/Zermelo%27s%20theorem%20%28game%20theory%29 | In game theory, Zermelo's theorem is a theorem about finite two-person games of perfect information in which the players move alternately and in which chance does not affect the decision making process. It says that if the game cannot end in a draw, then one of the two players must have a winning strategy (i.e. can force a win). An alternate statement is that for a game meeting all of these conditions except the condition that a draw is now possible, then either the first-player can force a win, or the second-player can force a win, or both players can at least force a draw.
The theorem is named after Ernst Zermelo, a German mathematician and logician, who proved the theorem for the example game of chess in 1913.
Example
Zermelo's Theorem can be applied to all finite-stage two-player games with complete information and alternating moves. The game must satisfy the following criteria: there are two players in the game; the game is of perfect information; the board game is finite; the two players can take alternate turns; and there is no chance element present. Zermelo has stated that there are many games of this type however his theorem has been applied mostly to the game chess.
When applied to chess, Zermelo's Theorem states "either White can force a win, or Black can force a win, or both sides can force at least a draw".
Zermelo's algorithm is a cornerstone algorithm in game-theory, however, it can also be applied in areas outside of finite games.
Apart from chess, Zermelo's theorem is applied across all areas of computer science. In particular, it is applied in model checking and value interaction.
Conclusions of Zermelo's theorem
Zermelo's work shows that in two-person zero-sum games with perfect information, if a player is in a winning position, then that player can always force a win no matter what strategy the other player may employ. Furthermore, and as a consequence, if a player is in a winning position, it will never require more moves than there are |
https://en.wikipedia.org/wiki/Robot%20control | Robotic control is the system that contributes to the movement of robots. This involves the mechanical aspects and programmable systems that makes it possible to control robots. Robotics can be controlled by various means including manual, wireless, semi-autonomous (a mix of fully automatic and wireless control), and fully autonomous (using artificial intelligence).
Modern robots (2000-present)
Medical and surgical
In the medical field, robots are used to make precise movements that are difficult for humans. Robotic surgery involves the use of less-invasive surgical methods, which are “procedures performed through tiny incisions”. Robots use the da Vinci surgical method, which involves the robotic arm (which holds onto surgical instruments) and a camera. The surgeon sits on a console where he controls the robot wirelessly. The feed from the camera is projected on a monitor, allowing the surgeon to see the incisions. The system is built to mimic the movement of the surgeon’s hands and has the ability to filter slight hand tremors. But despite the visual feedback, there is no physical feedback. In other words, as the surgeon applies force on the console, the surgeon won’t be able to feel how much pressure he or she is applying to the tissue.
Military
The earliest robots used in the military dates back to the 19th century, where automatic weapons were on the rise due to developments in mass production. The first automated weapons were used in World War I, including radio-controlled, unmanned aerial vehicles (UAVs). Since the invention, the technology of ground and aerial robotic weapons continues to develop, it transitioned to become part of modern warfare. In the transition phase of the development, the robots were semi-automatic, being able to be controlled remotely by a human controller. The advancements made in sensors and processors lead to advancements in capabilities of military robots. Since the mid-20th century, the technology of artificial intelligence |
https://en.wikipedia.org/wiki/Data%20URI%20scheme | The data URI scheme is a uniform resource identifier (URI) scheme that provides a way to include data in-line in Web pages as if they were external resources. It is a form of file literal or here document. This technique allows normally separate elements such as images and style sheets to be fetched in a single Hypertext Transfer Protocol (HTTP) request, which may be more efficient than multiple HTTP requests, and used by several browser extensions to package images as well as other multimedia contents in a single HTML file for page saving. , data URIs are fully supported by most major browsers, and partially supported in Internet Explorer.
Syntax
The syntax of data URIs is defined in Request for Comments (RFC) 2397, published in August 1998, and follows the URI scheme syntax. A data URI consists of:
data:content/type;base64,
The scheme, data. It is followed by a colon (:).
An optional media type. The media type part may include one or more parameters, in the format attribute=value, separated by semicolons (;) . A common media type parameter is charset, specifying the character set of the media type, where the value is from the IANA list of character set names. If one is not specified, the media type of the data URI is assumed to be text/plain;charset=US-ASCII.
An optional base64 extension base64, separated from the preceding part by a semicolon. When present, this indicates that the data content of the URI is binary data, encoded in ASCII format using the Base64 scheme for binary-to-text encoding. The base64 extension is distinguished from any media type parameters by virtue of not having a =value component and by coming after any media type parameters. Since Base64 encoded data is approximately 33% larger than original data, it is recommended to use Base64 data URIs only if the server supports HTTP compression or embedded files are smaller than 1KB.
The data, separated from the preceding part by a comma (,). The data is a sequence of zero or more octets re |
https://en.wikipedia.org/wiki/Carlos%20Sainz%3A%20World%20Rally%20Championship | Carlos Sainz: World Rally Championship is a 1990 racing video game co-developed by the Spanish companies Zigurat Software (previously known as Made in Spain) and Arcadia Software, and published by Zigurat for Amstrad CPC, MS-DOS, MSX and ZX Spectrum. Featuring Spanish rally driver Carlos Sainz and themed around rallying, the game pit players with races across various locations to qualify for the next couse in the World Rally Championship and modify characteristics of the Toyota Celica to accommodate each courses.
Carlos Sainz: World Rally Championship was created in conjunction with Sito Pons 500cc Grand Prix by most of the same team at Zigurat who worked on licensed sports titles such as Paris-Dakar (1988) and Emilio Sanchez Vicario Grand Slam with co-developer Arcadia, serving as their final release prior to abandoning the video game industry. The game originated during a meeting between Zigurat and Arcadia to discuss future projects, where various ideas were pitched. The idea of creating an accurate rally simulator came from motorsports being a hobby among Zigurat staff, with the programmers finding rally as a spectacular discipline and fitting due to graphic and dynamic possibilities. Zigurat hired Sainz, who had yet to become a world champion at the time, and development of the project started afterwards.
Carlos Sainz: World Rally Championship proved to be a success for Zigurat and garnered positive reception from critics across all platforms since its release; praise was given to the addictive gameplay, sense of speed, controls and sound but other reviewers felt mixed in regards to the graphics and difficulty, while the limited technical complexity was criticized. Conversions for Amiga and Atari ST were planned but never released. After its launch, Zigurat was contacted by Gaelco to work on a arcade game based on the World Rally Championship featuring Sainz before he changed teams from Toyota to Lancia near the end of development, being ultimately reworked a |
https://en.wikipedia.org/wiki/Acoustic%20interferometer | An acoustic interferometer is an instrument that uses interferometry to measure the physical characteristics of sound waves in a gas or liquid. It may be used to measure velocity, wavelength, absorption, or impedance of the sound waves. The principle of operation is that a vibrating crystal creates ultrasonic waves that are radiated into the medium being analyzed. The waves strike a reflector placed parallel to the crystal. The waves are then reflected back to the source and measured.
See also
Acoustic microscopy
Acoustic emission |
https://en.wikipedia.org/wiki/Fairchild%20660 | The Fairchild 660 is a tube-based single-channel audio compressor invented by Rein Narma and manufactured by the Fairchild Recording Equipment Corporation beginning in 1959. The 660 was the first intelligent automatic volume control limiter. The Fairchild 670, introduced shortly after the 660, is a dual-channel version. The rarity of Fairchild compressors has made them highly desirable and very valuable, with a used 660 now selling for $20,000 or more and a 670 selling for $30-$40,000 or more. They are commonly referred to as the "holy grail" of outboard gear.
History
The 660 was designed by Rein Narma, who had worked with Les Paul to build a recording mixer to use with Les Paul's Ampex 8-track. Les Paul asked Narma if he would build a compressor/limiter. Sherman Fairchild, who was friends with Les Paul, learned of the compressor and licensed Narma's compressor design, hiring Narma to be chief engineer at Fairchild Recording Equipment Corporation. The first 10 Fairchild 660 were built by Narma himself. The first unit was sold to Rudy Van Gelder who used it to cut lacquer masters for Blue Note Records and Vox Records. The second unit went to Olmsted Sound Studios in New York City, and the third 660 built went to Mary Ford and Les Paul.
Design
The mono 660 and dual-channel 670 can function as a compressor with a ratio of 2 to 1 and a threshold of 5 db below normal program level, as a peak limiter with a compression ratio of 30 to 1 and a threshold of 10 db above normal program level, or can operate anywhere between those two extremes. Utilizing a single push-pull stage of amplification and an extremely high control voltage, the sound of the 660 and 670 is characterized by the complete absence of audible thumps, with extremely low distortion and noise. Both feature an extremely fast attack time that can produce the full limiting effect during the first 1/10,000 of a second. This extremely fast attack time is combined with six different variable release timing curve |
https://en.wikipedia.org/wiki/Armstrong%20Audio | Armstrong Audio, originally called Armstrong Wireless and Television Ltd. was a British manufacturer of radios and other audio equipment based in London, England. Founded by Claude Charles Jackson in 1932.
History
Initially created to manufacture portable radios, during World War II their factory was used to manufacture radios, public address systems, and various electronic parts. After the war, they began to produce television sets, as well as long range radios for ships, but eventually ceased production of those lines to manufacture radios, amplifiers and tuners for home consumer use. In the 1950s when the high fidelity market began to take shape, the company name was changed to Armstrong Audio and they focused their marketing and manufacturing at becoming hi-fi specialists.
During the 1960s and 1970s they were extremely successful, creating several durable radio models which are still in use by consumers today, but by the end of the 1970s their lease on their factory ran out and it was decided not to invest in a new one. The building was torn down and the owners redeveloped it. Using plans developed for a further radio model, some of the staff continued on as Armstrong Amplifiers, but due to a lack of capital and suitable manufacturing space, production did not last long.
Today, what once was Armstrong Audio is now called Armstrong Hi-Fi and Video Services and is based in Walthamstow, and they provide maintenance contract to a number of retail stores.
Armstrong 521
The Armstrong 521 was a stereo hi-fi amplifier from the Armstrong Audio company and was marketed as 2 x 25W amplifier.
It employed germanium AL102 transistors in its output stages and these had a reputation for failure and are now unobtainable although it is possible, with modification to replace these with newer, silicon transistors. The amplifier was a single rail design and employed an electrolytic output capacitor in the output stage. The amplifier featured inputs for tape, tuner and MM g |
https://en.wikipedia.org/wiki/IBM%20WebSphere | IBM WebSphere refers to a brand of proprietary computer software products in the genre of enterprise software known as "application and integration middleware". These software products are used by end-users to create and integrate applications with other applications. IBM WebSphere has been available to the general market since 1998.
History
In June 1998, IBM introduced the first product in this brand, IBM WebSphere Performance Pack. this first component formed a part of IBM WebSphere Application Server Network Deployment.
Products
The following products have been produced by IBM within the WebSphere brand:
IBM WebSphere Application Server - a web application server
IBM Workload Deployer - a hardware appliance that provides access to IBM middleware virtual images and patterns
IBM WebSphere eXtreme Scale - an in-memory data grid for use in high-performance computing
IBM HTTP Server
IBM WebSphere Adapters
IBM Websphere Business Events
IBM Websphere Edge Components
IBM Websphere Host On-Demand (HOD)
IBM WebSphere Message Broker
Banking Transformation Toolkit
IBM MQ
IBM WebSphere Portlet Factory
IBM WebSphere Process Server
WebSphere Commerce (sold to HCL Technologies in 2019)
WebSphere Portal (sold to HCL Technologies in 2019) |
https://en.wikipedia.org/wiki/Qingjiang%20biota | The Qingjiang biota are a major discovery of fossilized remains dating from the early Cambrian period approximately 518 million years ago. The remains consist at least 20,000 individual specimens, and were discovered near the Danshui River in the Hubei province of China in 2019. The site is particularly notable due to both the large proportion of new taxa represented (approximately 53% of the specimens), and due to the large amount of soft-body tissue of the ancient specimens that was preserved, likely due to the organisms being rapidly covered in sediment prior to fossilization, that allowed for the detailed preservation of even fragile, soft-bodied creatures such as worms and jellyfish.
The site is a Burgess Shale type preservation, and has been widely compared to the Burgess Shale in terms of the site's richness and significance. The discovery has been described as one of the most significant of its kind in the last 100 years. Initial publications regarding the site stated that 4,351 of the collected specimens had been examined, and 101 species had been identified, 53 of which were new to science.
Talks are reportedly underway with local government to protect the site to ensure the longevity of continued research on the deposited specimens. |
https://en.wikipedia.org/wiki/Distcc | In software development, distcc is a tool for speeding up compilation of source code by using distributed computing over a computer network. With the right configuration, distcc can dramatically reduce a project's compilation time.
It is designed to work with the C programming language (and its derivatives like C++ and Objective-C) and to use GCC as its backend, though it provides varying degrees of compatibility with the Intel C++ Compiler and Sun Microsystems' Sun Studio Compiler Suite. Distributed under the terms of the GNU General Public License, distcc is free software.
Design
distcc is designed to speed up compilation by taking advantage of unused processing power on other computers. A machine with distcc installed can send code to be compiled across the network to a computer which has the distccd daemon and a compatible compiler installed.
distcc works as an agent for the compiler. A distcc daemon has to run on each of the participating machines. The originating machine invokes a preprocessor to handle header files, preprocessing directives (such as #ifdef) and the source files and sends the preprocessed source to other machines over the network via TCP either unencrypted or using SSH. Remote machines compile those source files without any local dependencies (such as libraries, header files or macro definitions) to object files and send them back to the originator for further compilation.
distcc version 3 supports a mode (called pump mode) in which included header files are sent to the remote machines,
so that preprocessing is also distributed.
Related software
distcc was an option for distributed builds in versions of Apple's Xcode development suite prior to 4.3, but has been removed.
Goma
Goma is a similar tool made by Google to replace distcc & ccache in compiling chromium.
Ccache
ccache is another tool aimed to reduce the compilation time by caching the output from the same input source files. ccache can also use distcc as its backend, providing |
https://en.wikipedia.org/wiki/Hermitian%20symmetric%20space | In mathematics, a Hermitian symmetric space is a Hermitian manifold which at every point has an inversion symmetry preserving the Hermitian structure. First studied by Élie Cartan, they form a natural generalization of the notion of Riemannian symmetric space from real manifolds to complex manifolds.
Every Hermitian symmetric space is a homogeneous space for its isometry group and has a unique decomposition as a product of irreducible spaces and a Euclidean space. The irreducible spaces arise in pairs as a non-compact space that, as Borel showed, can be embedded as an open subspace of its compact dual space. Harish Chandra showed that each non-compact space can be realized as a bounded symmetric domain in a complex vector space. The simplest case involves the groups SU(2), SU(1,1) and their common complexification SL(2,C). In this case the non-compact space is the unit disk, a homogeneous space for SU(1,1). It is a bounded domain in the complex plane C. The one-point compactification of C, the Riemann sphere, is the dual space, a homogeneous space for SU(2) and SL(2,C).
Irreducible compact Hermitian symmetric spaces are exactly the homogeneous spaces of simple compact Lie groups by maximal closed connected subgroups which contain a maximal torus and have center isomorphic to the circle group. There is a complete classification of irreducible spaces, with four classical series, studied by Cartan, and two exceptional cases; the classification can be deduced from Borel–de Siebenthal theory, which classifies closed connected subgroups containing a maximal torus. Hermitian symmetric spaces appear in the theory of Jordan triple systems, several complex variables, complex geometry, automorphic forms and group representations, in particular permitting the construction of the holomorphic discrete series representations of semisimple Lie groups.
Hermitian symmetric spaces of compact type
Definition
Let H be a connected compact semisimple Lie group, σ an automorphism of H |
https://en.wikipedia.org/wiki/UMANG | Unified Mobile Application for New-age Governance (UMANG) is a mobile app, a Digital India initiative of Ministry of Electronics and Information Technology (in short form MeitY), by the Government of India for access to central and state government services. The app supports 13 Indian languages and is available for Android, iOS and Windows.
The app is aimed at all citizens of India and offers hundreds of services including payment, registration, information search and application forms. It is a component of the Digital India initiative, intending to make government services available to the general public online and around the clock.
The app was developed by the Ministry of Electronics and Information Technology with the National e-Governance Division and launched in November 2017 by Prime Minister Narendra Modi at the Global Conference on Cyberspace in New Delhi. At launch the app offered 162 services from 33 state and central government departments and four states.
See also
Aarogya Setu
BharatNet
T App Folio
CoWIN |
https://en.wikipedia.org/wiki/Valve%20audio%20amplifier%20technical%20specification | Technical specifications and detailed information on the valve audio amplifier, including its development history.
Circuitry and performance
Characteristics of valves
Valves (also known as vacuum tubes) are very high input impedance (near infinite in most circuits) and high-output impedance devices. They are also high-voltage / low-current devices.
The characteristics of valves as gain devices have direct implications for their use as audio amplifiers, notably that power amplifiers need output transformers (OPTs) to translate a high-output-impedance high-voltage low-current signal into a lower-voltage high-current signal needed to drive modern low-impedance loudspeakers (cf. transistors and FETs which are relatively low voltage devices but able to carry large currents directly).
Another consequence is that since the output of one stage is often at ~100 V offset from the input of the next stage, direct coupling is normally not possible and stages need to be coupled using a capacitor or transformer. Capacitors have little effect on the performance of amplifiers. Interstage transformer coupling is a source of distortion and phase shift, and was avoided from the 1940s for high-quality applications; transformers also add cost, bulk, and weight.
Basic circuits
The following circuits are simplified conceptual circuits only, real world circuits also require a smoothed or regulated power supply, heater for the filaments (the details depending on if the selected valve types are directly or indirectly heated), and the cathode resistors are often bypassed, etc.
The common cathode gain stage
The basic gain stage for a valve amplifier is the auto-biased common cathode stage, in which an anode resistor, the valve, and a cathode resistor form a potential divider across the supply rails. The resistance of the valve varies as a function of the voltage on the grid, relative to the voltage on the cathode.
In the auto-bias configuration, the "operating point" is obtained by se |
https://en.wikipedia.org/wiki/Motorola%2056000 | The Motorola DSP56000 (also known as 56K) is a family of digital signal processor (DSP) chips produced by Motorola Semiconductor (later Freescale Semiconductor then NXP) starting in 1986 with later models are still being produced in the 2020s. The 56k series was quite popular for a time in a number of computers, including the NeXT, Atari Falcon030 and SGI Indigo workstations all using the 56001. Upgraded 56k versions are still used in audio equipment, radar systems, communications devices (like mobile phones) and various other embedded DSP applications. The 56000 was also used as the basis for the updated 96000, which was not commercially successful.
Technical description
The DSP56000 uses fixed-point arithmetic, with 24-bit program words and 24-bit data words. It includes two 24-bit registers, which can also be referred to as a single 48-bit register. It also includes two 56-bit accumulators, each with an 8-bit "extension" (aka headroom); otherwise, the accumulators are similar to the other 24/48-bit registers. Being a Modified Harvard architecture processor, the 56k has three memory spaces+buses (and on-chip memory banks in some of the models): a program memory space/bus and two data memory space/bus.
24 bits was selected as the basic word length because it gave the system a reasonable number range and precision for processing audio (sound), the 56000's main concern. 24 bits correspond to a large dynamic range, sufficient in the 1980s when analog-to-digital converters (ADCs) and digital-to-analog converters (DACs) rarely exceeded 20 bits. One example is ADSL applications, where filters typically require 20 bits of accuracy. The leftmost four bits are considered ample headroom for calculations.
The processor is capable of carrying out 16.5 Million Instructions Per Second (MIPS) at the maximum specified clock speed of , and has hardware support for block-floating point FFT. It uses TTL levels and consumes approximately
Applications and variants
In most des |
https://en.wikipedia.org/wiki/EHD3 | Eps15 homology domain-containing protein 3, abbreviated as EHD3 and also known as PAST3, is a protein encoded by the EHD3 gene. It has been observed in humans, mice and rats. It belongs to the EHD protein family, a group of four membrane remodeling proteins related to the Dynamin superfamily of large GTPases. Although the four of them are 70-80% amino acid identical, they all have different locations. Its main function is related to endocytic transport.
Structure
Primary structure
The primary structure of a protein is related to which amino acids a protein is made of. EHD3 has 535 amino acids, of which almost three-quarters are common in the four EHD proteins. This protein has a molecular mass of 60887 Daltons.
Secondary structure
The secondary structure of the EHD3 protein still remains unknown.
Tertiary structure
The tertiary structure of a protein involves the domains it is formed of. EHD3 protein is formed of four different domains:
EH domain-containing protein N-terminal, between the 24th and 56th amino acid. This is a short domain that can be found at the beginning of a protein, also known as N-terminus, of many dynamins and EF-hand domain-containing proteins.
Dynamin-type guanine nucleotide-binding (G) domain, between the 56th and 286th amino acid. It consists of a central eight-stranded beta-sheet surrounded by seven alpha helices and two one-turn helices. It is involved in the binding of magnesium ions (Mg2+) and GTP hydrolysis. GTP is joined to the protein through a nucleotide binding region, located between the 65th and 72nd amino acid.
EH domain, between the 444th and 532nd amino acid. It is found in all of the EHD proteins. The fold consists of two helix-loop-helix connected by a short antiparallel beta-sheet. The target peptide is bound in a hydrophobic region between two alpha helices. Apart from an EF-hand domain, it can also include tyrosine phosphorylation sites and coiled coils. This domain is often related to the regulation of protein t |
https://en.wikipedia.org/wiki/Continuous%20mapping%20theorem | In probability theory, the continuous mapping theorem states that continuous functions preserve limits even if their arguments are sequences of random variables. A continuous function, in Heine’s definition, is such a function that maps convergent sequences into convergent sequences: if xn → x then g(xn) → g(x). The continuous mapping theorem states that this will also be true if we replace the deterministic sequence {xn} with a sequence of random variables {Xn}, and replace the standard notion of convergence of real numbers “→” with one of the types of convergence of random variables.
This theorem was first proved by Henry Mann and Abraham Wald in 1943, and it is therefore sometimes called the Mann–Wald theorem. Meanwhile, Denis Sargan refers to it as the general transformation theorem.
Statement
Let {Xn}, X be random elements defined on a metric space S. Suppose a function (where S′ is another metric space) has the set of discontinuity points Dg such that . Then
where the superscripts, "d", "p", and "a.s." denote convergence in distribution, convergence in probability, and almost sure convergence respectively.
Proof
This proof has been adopted from
Spaces S and S′ are equipped with certain metrics. For simplicity we will denote both of these metrics using the |x − y| notation, even though the metrics may be arbitrary and not necessarily Euclidean.
Convergence in distribution
We will need a particular statement from the portmanteau theorem: that convergence in distribution is equivalent to
for every bounded continuous functional f.
So it suffices to prove that for every bounded continuous functional f. Note that is itself a bounded continuous functional. And so the claim follows from the statement above.
Convergence in probability
Fix an arbitrary ε > 0. Then for any δ > 0 consider the set Bδ defined as
This is the set of continuity points x of the function g(·) for which it is possible to find, within the δ-neighborhood of x, a point which maps |
https://en.wikipedia.org/wiki/Experimental%20language | An experimental language is a constructed language designed for linguistics research, often on the relationship between language and thought.
One particular assumption having received much attention in fiction is popularly known as the Sapir–Whorf hypothesis. The claim is that the structure of a language somehow affects the way its speakers perceive their world, either strongly, in which case "language determines thought" (linguistic determinism), or weakly, in which case "language influences thought" (linguistic relativity). (For a list of languages that are merely mentioned, see the relevant section in List of constructed languages.)
The extreme case of the strong version of the hypothesis would be the idea that words have a power inherent to themselves such that their use determines not just our thoughts, but even that which our thoughts are about, i.e. reality itself. This idea, however, is more properly treated within ontology than linguistics.
Languages exploring the Sapir–Whorf hypothesis
Constructed languages
Láadan was designed by linguist Suzette Haden Elgin in her science fiction novel Native Tongue, about a patriarchal society in which the overriding priority of the oppressed women is the secret development of a "feminist" language, Láadan, to aid them in throwing off their shackles.
Loglan, by James Cooke Brown, was designed for linguistic research with the specific goal of making a language so different from natural languages that people learning it would think in a different way if the hypothesis were true.
Lojban is the successor of Loglan and has the same goals.
Toki Pona, by Sonja Lang (née Kisa), is inspired by Taoist philosophy, among other things, and designed to shape the thought processes of its users in Zen-like fashion.
Fictional languages
Named
Babel-17, by Samuel R. Delany, is centered on a fictional language that denies its speakers independent thought, forcing them to think purely logical thoughts. This language is used as a |
https://en.wikipedia.org/wiki/17th%20meridian%20west | The meridian 17° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Greenland, Iceland, the Atlantic Ocean, Africa, the Southern Ocean, and Antarctica to the South Pole.
The 17th meridian west forms a great circle with the 163rd meridian east.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 17th meridian west passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="125" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
|
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Atlantic Ocean
| style="background:#b0e0e6;" | Greenland Sea — passing just east of Shannon Island, (at )
|-
|
! scope="row" |
|
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Atlantic Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Island of Madeira
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Atlantic Ocean
| style="background:#b0e0e6;" | Passing just west of the island of Tenerife, (at ) Passing just east of the island of La Gomera, (at )
|-valign="top"
|
! scope="row" | Western Sahara
| Ras Nouadhibou peninsula — claimed by and the
|-
|
! scope="row" |
| Ras Nouadhibou peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Atlantic Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
|
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Atlantic Ocean
| style="background:#b0e0e6;" |
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Southern Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" | Antarctica
| Queen Maud Land, claimed by
|-
|}
See also
16th meridian west
|
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