Qswitching , sometimes known as giant pulse formation , is a technique by which a laser can be made ... for pulse generation with lasers, Qswitching leads to much lower pulse repetition rates, much higher ... lense modelocked ti sa with aom cavity dumper Qswitching was first proposed in 1958 by Gordon ... of QswitchingQswitching is achieved by putting some type of variable Attenuator electronics ... pulse , which may have a very high peak intensity. There are two main types of Qswitching Active Qswitching Here, the Q switch is an externally controlled variable attenuator. This may be a mechanical ..., producing a Q switched pulse that has characteristics inherited from the seed. Passive Qswitching ... Cr YAG , which is used for Qswitching of Nd YAG laser Nd YAG lasers , a bleachable dye, or a passive ... Qswitching. Variants image Regenerative Amplifier.png thumb right Regenerative amplifier. Red line ... the cavity all at once. This produces a shorter output pulse than regular Qswitching. Electro optic ... is more complicated to align than simple Qswitching, and may need a Control system control loop to choose ... QSwitching Category Laser science ca Commutaci Q cs Q sp n n de G teschalter he Q Switch nl Q switch ja Q ru sv Qswitching uk ... inside the cavity corresponds to a decrease in the Q factor or quality factor of the optical resonator . A high Q factor corresponds to low resonator losses per roundtrip, and vice versa. The variable attenuator is commonly called a Q switch , when used for this purpose. Initially the laser medium is Laser pumping pumped while the Q switch is set to prevent feedback of light into the gain medium producing an optical resonator with low Q . This produces a population inversion , but laser operation ... saturated . At this point, the Q switch device is quickly changed from low to high Q, allowing feedback ... increase of Q is triggered by an external event, typically an electrical signal. The pulse repetition ... more details
wiktionary switchingSwitching may refer to switch , electrical switching telephone exchange , telephone switching Packet switching , switching of digital networks LAN switching railroad switch , railroad turnouts shunt rail , the process of switching rail cars Switching film , a 2003 Danish interactive film Class switching , Immunoglobulin class switching or isotype switching or isotypic commutation or class switch recombination CSR in immunology disambiguation ja pl Komutacja ru ... more details
present in the laser for a short time, which results in a pulsed output. Qswitching is more commonly ... also Qswitching Modelocking References Reflist DEFAULTSORT Gain Switching Category Laser science ...Gain switching is a technique in optics by which a laser can be made to produce pulses of light of extremely short duration, of the order of picoseconds 1 E 12 s 10 sup 12 sup s . ref K. Y. Lau, Gain switching of semiconductor injection lasers ,Appl. Phys. Lett.,vol. 52, iss. 4, pp. 257 259 1988 ref ref P. Vasil ev, Ultrafast Laser Diodes Fundamentals and Applications , Artech House, London, 1995 ref div style float right width 424px margin 0 0 1em 1em Image gainswitchpulse.png Pulse generated by gain switching div In a semiconductor laser , the optical pulses are generated by injecting a large number of carriers electrons into the active region of the device, bringing the carrier density within that region from below to above the lasing threshold . When the carrier density exceeds that value, the ensuing stimulated emission results in the generation of a large number of photons. However, carriers are depleted as a result of stimulated emission faster than they are injected. So the carrier density eventually falls back to below lasing threshold which results in the termination of the optical output. If carrier injection has not ceased during this period, then the carrier density in the active region can increase once more and the process will repeat itself. The figure on the right shows a typical pulse generated by gain switching with a sinusoidal injection current at 250 MHz producing a pulse of approximately 50 ps. The carrier density is depleted during the pulse, and subsequently rises due to continued current injection, producing a smaller secondary pulse ... s, gain switching or synchronous pumping usually involves the laser gain medium being Laser pumping ... can be achieved. The term gain switching derives from the fact that the optical gain is negative when ... more details
uc Q lc qQ English alphabet Letter names named cue IPAc en k ju ref Q Oxford English Dictionary ... . History class wikitable bgcolor EEEEEE Egyptian hieroglyph br wj Phoenician br qoph Etruscan Q ... based on an Egyptian hieroglyph was IPA q voiceless uvular plosive , a sound common to Semitic ... and Q were all used to represent the sounds k and g which were not differentiated in writing . Of these, Q .... Later, the use of C and its variant G replaced most usages of K and QQ survived only to represent ... used Q in conjunction with V to represent IPA k Usage In most modern western languages written in Latin script, such as in Romance language Romance and Germanic languages , q appears almost ... Q not followed by U Q without U . In English language English this digraph most often denotes the cluster IPA kw , except in borrowings from French where it represents IPA k as in plaque . Q is the second most rarely used letter in the English alphabet . In script written English, the capital Q is very close in appearance to a 2, and many people use the print Q instead. In Albanian language Albanian , q represents the voiceless palatal plosive IPA c . In Azerbaijani language Azeri , q represents the voiced velar plosive IPA . In Chinese language Chinese Hanyu Pinyin , q is used to represent ... of the mouth. In Fijian language Fijian , q represents the Prenasalized consonant prenasalized ... language Aymara , q represents the voiceless uvular plosive IPA q . In Italian language Italian qu represents IPA kw where IPA w is the semivowel allophone of IPA u . In Kiowa language Kiowa , q represents a glottalized velar plosive IPA k . In Maltese language Maltese and V ro , q represents ... , q represents the voiceless uvular plosive IPA q . In Xhosa language Xhosa and Zulu language Zulu , q represents the postalveolar click IPA k . File Q and g comparison.svg thumb right 150px A comparison of q and g. This image belongs with the text below, but is placed here so that it does not run ... more details
The term switching station may refer to a electrical substation , with only one voltage level, whose only function are switching actions. a Charging station Battery swapping battery switch station , such as the ones used by the Better Place network. a Rail yard railroad switching station . a telephone exchange telephone switching station . disambig ... more details
Unreferenced date October 2008 An adaptive switch is designed to operate in cut through mode cut through switching normally but if a port s error rate jumps too high, the switch automatically reconfigures the port to run in store and forward mode This optimizes the switch s performance by providing higher speed cut through switching switching if error rates are low but higher throughput store and forward switching if error rates are high. Adaptive switching is typically done on a port by port basis. See also Network switch Ethernet Store and forward Fragment free Cut through switching Category Computer networking compu hardware stub cs Adaptive switching ... more details
refimprove date November 2011 Orphan date February 2009 Q Be is a digital audio player manufactured in South Korea . It is imported in the United Kingdom and sold in many of the large electronic stores such as Currys . It has an Organic light emitting diode display. ref cite news url http www.highbeam.com doc 1G1 139020853.html title Hot New Product Supportplus Q BE. The smallest music player in the world? last Reid first Rory date 24 November 2005 work Computer Act ve accessdate 25 November 2011 ref It is available in 256Mb, 512Mb and 1Gb memory variants. Its built in battery electricity battery is recharged using the same USB cable that is used to transfer data to the device, the cable is inserted into the headphone socket. The Q Be is identical to the MobiBLU DAH 1500i . When introduced, Q Be claimed to be the world s smallest DAP in terms of cubic volume, although the player itself is cubical and therefore thicker than all of Apple s iPods . In September 2006 Apple launched their iPod Shuffle, which is smaller in overall size and volume Citation needed date February 2007 than the Q Be but lacking a display. See also Cube2 References reflist Category Digital audio players product stub ... more details
Infobox television show name Q A image caption show name 2 genre Current affairs news format Current affairs creator producer Tim Watkin creative director developer presenter Paul Holmes broadcaster Paul Holmes voices narrated theme music composer opentheme endtheme composer country New Zealand language English language English num seasons num episodes list episodes executive producer producer supervising producer asst producer co producer editor story editor location TVNZ Centre Auckland , New Zealand cinematography camera runtime 60 minutes network TVNZ picture format 576i Standard definition television SDTV first run first aired last aired preceded by Agenda TVNZ programme Agenda followed by related website http tvnz.co.nz q and a news Q A is a New Zealand current event and political talkshow. ref http tvnz.co.nz q and a news ref It is hosted by Paul Holmes broadcaster Paul Holmes , with interviews conducted by Guyon Espiner and expert analysis with Therese Arseneau . The show airs live from the TVNZ Centre on Sundays from 9 to 10am on TV One New Zealand TV ONE , and reshows later that day from 9 10pm to 10 00pm on TVNZ 7 . History Q A premiered on the 22 March 2009 as a replacement for Agenda TVNZ programme Agenda . Following the death of Holmes mother, Mark Sainsbury filled in for one week. ref http tvnz.co.nz q and a q and s2 e5 video 2917174 ref Format The programme starts off every week with a week that was style run through of the main political events that week. Holmes will then introduce the panel usually made up of Arseneau and a political observer and a former politician Following that Espiner will conduct an interview with a politician either in the studio or on location and Holmes will lead the panel through a discussion about the responses the interviewee gave. After an ad break Holmes will conduct a more relaxed interview with a former politician or political observer, with Holmes again leading the panel through discussing what will be the big stories ... more details
In a packet switched computer network network , burst switching is a capability in which each network switch extracts routing instructions from an incoming Packet information technology packet header information technology header to establish and maintain the appropriate switch telecommunication connection connection for the duration of the packet, following which the connection is automatically released. In concept, burst switching is similar to connectionless mode transmission , but differs in that burst switching implies an intent to establish the switch connection in near real time so that only minimum buffering is required at the node networking node switch. A variant of burst switching used in optical network s is optical burst switching . Source from Federal Standard 1037C Category Computer networks compu network stub ... more details
No footnotes date August 2009 Lead too short date August 2009 Switching barriers or switching costs are terms ... s changing of suppliers. In many market s, consumer s are forced to incur cost s when switching from one Supply and demand supplier to another. These costs are called switching costs and can come in many different shapes. Definition The definition of switching costs is quite broad. Thompson and Cats Baril 2002 Citation needed date April 2009 defines switching costs as the costs associated with switching supplier , while Farrell and Klemperer 2007 write that a consumer faces a switching ... seller . As these definitions indicate, switching costs can arise for several different reasons. Examples of switching costs include the effort needed to inform friends and relatives about a new telephone ... switching to a new electricity provider. Types of switching costs include exit fees, search costs ..., the psychological, emotional, and social costs of switching are often overlooked or underestimated ... to hook into a phone line. Switching costs are a major reason for pursuing orders of magnitude ... strategy has been called Andrew Grove Andy Grove s 10x rule. Where switching costs for a buyer are prohibitively ..., a bilateral monopoly . However, Shalev and Asbjornsen found that Switching Costs is not a relevant ... be avoided in the public sector, switching costs are always incurred, and so switching costs would not be a relevant ..., 10 3 428 452. ref Competition, collective switching costs, and market performance Switching costs affect competition . When a consumer faces switching costs, the rational consumer will not switch to the Supply and demand supplier offering the lowest price if the switching costs in terms of monetary ... from switching. QWERTY example Competition is also influenced by collective switching costs, especially in markets with strong network effects . Collective switching costs are the combined switching costs of all users in a particular market. For example, the QWERTY keyboard layout illustrates ... more details
In telecommunications , message switching was the precursor of packet switching , where messages were routed in their entirety, one hop at a time. It was first introduced by Leonard Kleinrock in 1961. Message switching systems are nowadays mostly implemented over packet switched or circuit switched data network s. Each message is treated as a separate entity. Each message contains addressing information, and at each switch this information is read and the transfer path to the next switch is decided ... application for Message Switching. A delay in delivering email is allowed unlike real time ... of message switching systems. When this form of switching is used, no physical path is established ..., it is stored in the first switching office i.e. Router computing router then forwarded later ... by the message switching networks. A message switch is transactional . It can store data or change ... form at the receive end. Message switching multiplexes data from different sources onto a common facility. A message switch is a one of the switching technology. In message switching, when a message consists of a block of data to be sent, it is stored in the first switching office i.e. router and then forwarded ... and forward delays Since message switching stores each message at intermediate nodes in its entirety ... will be experienced along the message path. In a message switching centre an incoming message is not lost ... route and retransmitted when the required circuit becomes free. Message switching is thus an example of a delay system or a queuing system. Message switching is still used for telegraph traffic and a modified form of it, known as packet switching, is used extensively for data communications. Advantages The advantages to Message Switching are Data channels are shared among communication ... switching Message Oriented Middleware message oriented middleware References Leonard Kleinrock, http ... mk Message switching pl Komutacja wiadomo ci pt Comuta o de mensagens zh ... more details
This article addresses packet switching in computer network s. LAN switching is a form of packet switching used in local area network s. Switching technologies are crucial to network design, as they allow ... 2 switching Data Link Layer Layer 2 switching uses the media access control address MAC address ... switching is hardware based, ref http www.techsoftcomputing.com internetworkdesign nd2002.html wp3310 ... is as a multiport network bridge bridge . Layer 2 switching provides the following Hardware based bridging MAC Wire speed High speed Low latency Low cost Layer 2 switching is highly efficient because ... 2 switching is used for workgroup connectivity and network segmentation breaking up collision domain ... networks. Layer 2 switching has helped develop new components in the network infrastructure Server ... switches cannot completely replace routers in the internetwork. Layer 3 switching The only difference ... decisions, and the switch performs only hardware based packet switching. However, some traditional routers ... effectively replace routers. Layer 3 switching is all hardware based packet forwarding, and all packet ... of layer 3 switching include the following Hardware based packet forwarding High performance packet switching High speed scalability Low Lag latency Lower per port cost Flow accounting Security Quality of service QoS SWITCHING The switching algorithm is relatively simple and is the same for most ... executes the same switching process. As the packet moves through the internetwork, its physical address ... are also called as autonomous systems. Layer 4 switching Layer 4 switching is considered a hardware based layer 3 switching technology that can also consider the application used for example, Telnet or FTP . Layer 4 switching provides additional routing above layer 3 by using the port number s found ... like NetFlow switching in Cisco s higher end routers. The largest benefit of layer 4 switching .... Multi layer switching MLS main Multilayer switch Multi layer switching combines layer 2, 3, and 4 ... more details
Cleanup date June 2007 Label switching is a technique of computer network network relaying to overcome the problems perceived by traditional internet protocol IP table switching also known as traditional layer 3 hop by hop routing ref cite web url http www.linktionary.com l label switching.html title Label Switching Linktionary term publisher Linktionary.com date accessdate 2012 03 28 ref . Here, the switching of network packet information technology packets occurs at a lower OSI protocols level , namely the data link layer rather than the traditional network layer . Each packet is assigned a label number and the switching takes place after examination of the label assigned to each packet. The switching is much faster than IP routing . New technologies such as Multiprotocol Label Switching MPLS use label switching. The established Asynchronous Transfer Mode ATM protocol also uses label switching at its core. According to RFC 2475 An Architecture for Differentiated Services, December 1998 Examples of the label switching or virtual circuit model include Frame Relay, ATM, and MPLS. In this model path forwarding state and traffic management or Quality of Service QoS state is established for traffic streams on each hop along a network path. Traffic aggregates of varying granularity are associated with a label switched path at an ingress node, and packets cells within each label switched path are marked with a forwarding label that is used to look up the next hop node, the per hop forwarding behavior, and the replacement label at each hop. This model permits finer granularity resource allocation to traffic streams, since label values are not globally significant but are only significant ... on a link with a particular label, and the label switching semantics govern the next hop selection ... topic is Multilayer Switching, which discusses silicon based wire speed routing devices that examine ... de Label Switching ... more details
Prey switching is Frequency dependent selection frequency dependent predation, where the predator preferentially ... morphs. In comparison, prey switching has been used when describing the choice between different .... Soc. B 319, 485 503 ref Definition The term switching was first coined by the ecologist Murdoch ... type of prey. ref Murdoch,W.W. 1969 Switching in generalist predators experiments on prey specificity ... prey switching has mainly been used by ecologists, while apostatic selection has been used ... dependent selection. One of the ways prey switching has been identified and defined is when a predator ... which are rare. The definition of preference will therefore impact on understanding switching. The most ... time with N1 N2 , prey switching is presumed to occur. The opposite of prey switching is when a predator ... increases. This opposite phenomenon has been called negative prey switching, or anti apostatic selection when it refers to the choice between different morphs. Prey switching has been in the scientific ... in prey switching has fallen since it is hard to demonstrate whether it has or is occurring. ref Hassell ... predation Switching in the 15 spines Stickleback, Spinachia spinachia. J. Anim. Ecol. 62, 341 352. ref ref Cornell, H. 1976 Search strategies and the adaptive significance of switching in some general ... mechanisms help to demonstrate how prey switching and apostatic selection fit into over arching ecological ... can account for switching behaviour. In experiments with Guppies the switching behaviour displayed was due to the choice of patch. ref Murdoch, W.W. et al. 1974 Switching in Predatory Fish. Ecology 56, 1094 1105 ref Likewise the switching behaviour of stoneflies was due to the time they were active. ref Elliott, J.M. 2004 Prey switching in four species of carnivorous stoneflies. Freshwater Biol. 49, 709 720. ref The formation of a search image may also lead to the consumer switching which prey ... for the switching behaviour displayed by Bombus pennsylvanicus , however they are reluctant to use ... more details
For a frequency synthesizer , the switching time or more colloquially the switching speed is the amount of time from when the command for the next frequency is requested until the time that the synthesizer s output becomes usable and meets the specified requirements. Such requirements will vary depending on the design of the synthesizer. In the 1970s switching speeds ranged from 1 milli sec to 10 micro seconds. A more general statement has been given by James A. Crawford 50 reference cycles as a general rule of thumb. By this rule, a reference frequency of 50 kHz has a settling time of 1 milli seconds. ref Craw1994 Crawford, 1994, p. 303 ref Two other authors state Hamid Rategh and Thomas H. Lee engineering professor Thomas H. Lee that the switching time i.e., settling time is a function of the percentage change in the feedback division ratio. ref Rategh2001 Rategh, 2001, p. 25 ref So according to them, the delta N over N itself determines the switching time, where N is the frequency synthesizer s feedback divisor. References Reflist Further reading cite id Craw1994 Crawford, James A. 1994. Frequency Synthesizer Design Handbook , Artech House, ISBN 0 89006 440 7 cite cite id Rategh2001 Rategh, Hamid and R. Lee, Thomas H. Stanford University 2001. Multi GHz Frequency Synthesis & Division Frequency Synthesizer Design for 5 GHz Wireless LAN Systems , Kluwer, ISBN 0 7923 7533 5 cite Category Oscillators Engineering stub ... more details
Packet switching is a digital networking communications method that groups all transmitted data &ndash ... packets . Packet switching features delivery of variable bit rate data streams sequences of packets ... load in the network. Packet switching contrasts with another principal networking paradigm, circuit switching , a method which sets up a limited number of dedicated connections of constant bit rate ... fees as opposed to flat rate , for example in cellular communication services, circuit switching ... packet switching is characterized by a fee per unit of information. Two major packet switching modes exist 1 Connectionless communication connectionless packet switching, also known as datagram switching, and 2 Connection oriented communication connection oriented packet switching, also known as virtual circuit switching. In the first case each packet includes complete addressing or routing information ... packet switching below . Packet mode communication may be utilized with or without intermediate forwarding ... or data streams. Statistical multiplexing, packet switching and other store and forward buffering ... scheme. Multiplex techniques History The concept of switching small blocks of data was first explored ... in packet switching, and published a book in the related field of digital message switching ... switching during his research at the RAND Corporation for the US Air Force into survivable communications ... last Stewart first Bill title Paul Baran Invents Packet Switching work Living Internet date 2000 01 ... by store and forward switching. Baran s study made its way to Robert Taylor computer ... the feasibility of packet switching. The NPL Data Communications Network entered service in 1970. Roberts and the ARPANET team took the name packet switching itself from Davies s work. The first computer network and packet switching network deployed for computer resource sharing was the Octopus Network ... for sharing resources using packet switching among the nodes. Connectionless and connection oriented ... more details
Unreferenced date September 2009 A Switching loop or Bridge loop occurs in computer network s when there is more than one Layer 2 OSI model path between two endpoints e.g. multiple connections between two network switch es or two ports on the same switch connected to each other . The loop creates broadcast radiation as broadcasts and multicast s are forwarded by switches out every Computer port hardware port , the switch or switches will repeatedly rebroadcast the broadcast messages flooding the network. Since the Layer 2 header does not support a time to live TTL value, if a frame is sent into a looped topology, it can loop forever. A physical topology that contains switching or bridge loops is attractive for redundancy reasons, yet a switched network must not have loops. The solution is to allow physical loops, but create a loop free logical topology using the spanning tree protocol STP on the network switches. Broadcasts In the case of broadcast packets broadcast radiation over a switching loop, the situation may develop into a broadcast storm . MAC database instability Switching loops can cause misleading entries in a switch s Media Access Control MAC database and can cause endless unicast call stack frames to be broadcast throughout the network because if there was a single broadcast, the switch thinks that on both connected ports is the same host like at a single other port the correct port this happens because both ports received the broadcast packet with the sender address of the host . In a redundant switched network it is possible for switches to learn the wrong information. A switch can incorrectly learn that a MAC address is on one port, when it is actually on a different ... a switching loop packets will circulate the network until their time to live TTL value expires as no TTL concept exists at Layer 2 . DEFAULTSORT Switching Loop Category Network performance Category Network topology compu network stub de Switching Loop ... more details
No footnotes date June 2009 Circuit switching is a methodology of implementing a telecommunications network ... between the two telephones, for as long as the call lasts. Circuit switching contrasts with packet switching which divides the data to be transmitted into Network packet packets transmitted through the network independently. In packet switching, instead of being dedicated to one communication session ..., resulting in the loss of the quality of service guarantees that are provided by circuit switching. In circuit switching, the bit delay is constant during a connection, as opposed to packet switching ..., the channel remains reserved and protected from competing users. Virtual circuit switching is a packet switching technology that emulates circuit switching, in the sense that the connection is established before any packets are transferred, and packets are delivered in order. While circuit switching ... the actual circuit data. Early telephone exchanges are a suitable example of circuit switching ... were in fact not talking and the line was silent. Compared to datagram packet switching Circuit switching contrasts with packet switching which divides the data to be transmitted into small units, called packets, transmitted through the network independently. Packet switching shares available ... calls. In circuit switching, and virtual circuit switching, a route and bandwidth is reserved from source to destination. Circuit switching can be relatively inefficient because capacity is guaranteed ..., the connection is immediately available while established. Packet switching is the process of segmenting ... in the correct order, based on the packet number. Datagram packet switching networks do not require ... optical mesh network See also Packet switching Message switching Call telecommunications Clos network Time Driven Switching Connection oriented Switching circuit theory External links http www.wired.com ... de circuitos fa fr Commutation de circuits ko id Circuit switching it Multiplazione ... more details
language sociolinguistics In linguistics , code switching is the concurrent use of more than one language ... other. Thus, code switching is the use of more than one linguistic variety in a manner consistent with the syntax and phonology of each variety. Code switching is distinct from other language contact ... language. On the other hand, speakers practice code switching when they are each fluent in both languages. Code mixing is a thematically related term, but the usage of the terms code switching and code ... mixing to denote the formal linguistic properties of said language contact phenomena, and code switching ... last Clyne first Michael year 2000 chapter Constraints on code switching how universal are they? editor1 ... called code switching a sub standard language usage. ref name Weinreich Cite book last Weinreich first ... Monolingual and bilingual acquisition. Old Tappan, NJ Merrill Prentice Hall. ref The term code switching ... Zone Code Switching Strategies by Latino a Writers journal Melus volume 32 year 2007 pages 75 96 issue 1 ref In popular usage code switching is sometimes used to refer to relatively stable informal ... . ref name Zentella Both in popular usage and in sociolinguistic scholarship, the name code switching is sometimes used to refer to switching among dialect s, style shifting styles or Register sociolinguistics ... Matters pages 157 167 isbn 1 85359 167 X ref Social motivations for code switching Code mixing links here Code switching relates to, and sometimes Indexicality indexes social group membership ... switching behaviours and Social class class , ethnicity , and other social positions. ref See Cite ..., scholars in interactional linguistics and conversation analysis have studied code switching as a means ... The Why and How Questions in the Analysis of Conversational Codeswitching title Code Switching in Conversation ... Sequential Versus Identity Related Explanation in Code Switching title Code Switching in Conversation ... Some Implications of Code Switching for Overlap Resolution journal Research on Language and Social ... more details
Bank switching is a technique to increase the amount of usable memory beyond the amount directly addressable ... a system from diskette could be switched out when no longer needed. Bank switching originated in minicomputer ... Graw Hill, 1971 page 156 ref Many modern microcontroller s and microprocessor s use bank switching ... in small embedded system s. The technique was common in 8 bit microcomputer systems. Bank switching ... use a bank switching technique to access internal I O and control registers, which limits the number ... Bank switching can be considered a way of extending the address bus of a processor with some ... I O addresses , an output address may be decoded. Several bank switching control bits could be gathered ... do a bank switching operation to access large memory objects. There are other limitations. Generally a bank switching system will have one block of program memory that is common to all banks no matter ... to process interrupt s. Unlike a virtual memory scheme, bank switching must be explicitly managed ... of which memory bank holds a required piece of data, and then call the bank switching routine to make ..., Que Books, 1992, ISBN 0 88022 856 3 pages 699 700 ref However, bank switching can access data much ... system must manage the bank switching operation to ensure that program execution can continue ... of CP M released in 1982 supported bank switching to allow use of more than the 64K of memory that the 8080 ... , Info World October 25, 1982 page 1 ref Bank switching allowed extra memory and functions to be added to a computer design without the expense and incompatibility of switching to a processor with a wider address bus . For example, the Commodore 64 C64 used bank switching to allow for a full 64KB of RAM ... of bank switching technique that allows more than the 640 KB of RAM defined by the original ..., simulating bank switching for memory above 1 MB called extended memory , which is not directly ..., but in every other way it works like the bank switching of EMS, from the perspective of a program that uses ... more details
Infobox film name Switching Channels image Switching Channels.jpg image size 200px caption Theatrical release poster director Ted Kotcheff producer Martin Ransohoff writer Jonathan Reynolds br Play br Ben Hecht br Charles MacArthur narrator starring Kathleen Turner br Burt Reynolds br Christopher Reeve music Michel Legrand cinematography Fran ois Protat editing Thom Noble studio Switching Channels Inc. distributor TriStar Pictures released start date 1988 3 4 runtime 105 minutes country United States language English budget 19 million gross 9,129,999 preceded by followed by Switching Channels is a 1988 American comedy film remake of The Front Page also more famously remade as His Girl Friday in 1940 . It stars Kathleen Turner as Christy Colleran, Burt Reynolds as John L. Sullivan IV, Christopher Reeve as Blaine Bingham, Ned Beatty as Roy Ridnitz, Henry Gibson as Ike Roscoe, and George Newbern as Sigenthaler. The film was notorious for its harsh infighting between Reynolds and Turner during filming, and the film was seen as a failure, commercially and critically. It is available on DVD ... primarily in Canada with a Canadian director Ted Kotcheff , Switching Channels features many popular ... gave Switching Channels mixed results Roger Ebert Ebert was positive about the film and liked how ... Switching Channels a thumbs down. ref cite web title Switching Channels film review from At the Movies ... tv buenavista ebertandroeper index2.html ?sec 6&subsec switching channels accessdate May 9, 2009 ref Rotten Tomatoes currently lists Switching Channels with a 56 rating. ref cite web title Switching Channels movie reviews publisher Rotten Tomatoes url http www.rottentomatoes.com m switching channels ... . External links imdb title id 0096203 title Switching Channels Amg movie 48201 Switching Channels Mojo title switchingchannels Switching Channels References references Ted Kotcheff Category 1988 ... ru simple Switching Channels ... more details
Phenotypic switching a.k.a. phenotypic dimorphism is switching between two cell types. An example is Candida albicans , which, when it infects host tissue, switches from the usual unicellular yeast like form into an invasive, multicellular filamentous form. ref cite journal author Kumamoto CA, Vinces MD title Contributions of hyphae and hypha co regulated genes to Candida albicans virulence journal Cell. Microbiol. volume 7 issue 11 pages 1546 54 year 2005 pmid 16207242 doi 10.1111 j.1462 5822.2005.00616.x ref This switching between two cell types is known as dimorphism. Phenotypic switching in C. albicans include the switch from white cells to opaque cells in need for sexual mating. References Reflist External links cite journal author Neville SE, Baigent S, Lowry PJ title Are Hox genes responsible for the phenotypic switching and zonation of the adult adrenal cortex? journal Endocrine Abstracts volume 2 pages 52 date December 2001 url http www.endocrine abstracts.org ea 0002 ea0002p52.htm cite journal author D Souza CA, Heitman J title It infects me, it infects me not phenotypic switching in the fungal pathogen Cryptococcus neoformans journal J. Clin. Invest. volume 108 issue 11 pages 1577 8 year 2001 month December pmid 11733551 pmc 200997 doi 10.1172 JCI14497 url http www.jci.org cgi content full 108 11 1577 cite journal author Sonneborn A, Tebarth B, Ernst JF title Control of white opaque phenotypic switching in Candida albicans by the Efg1p morphogenetic regulator journal Infect. Immun. volume 67 issue 9 pages 4655 60 date 1 September 1999 pmid 10456912 pmc 96790 url http iai.asm.org cgi pmidlookup?view long&pmid 10456912 cite conference author Javan C, Shaunak S title Repeated phenotypic switching of HIV 1 in AIDS patients sampled regularly over 2 years. booktitle 4th Conference on Retroviruses and Opportunistic Infections date January 22 26, 1997 location Washington, DC url http www.aegis.com conferences croi 1997 450.html DEFAULTSORT Phenotypic Switching Category ... more details
Distributed switching is an architecture in which multiple central processing unit processor controlled switching units are distributed. There is often a hierarchy of switching elements, with a centralized Server computing host Stored Program Control exchange switch and with remote switches located close to concentrations of users. Use in telephony networks Distributed switching is often used in telephone network s, though it is often called host remote switching . In rural areas, population centers tend to be too small for economical deployment of a full featured dedicated telephone exchange , and distances between these centers make transmission telecommunications transmission costs relatively high. Normal telephone traffic patterns show that most calling is done between people in a community of interest , in this case a geographical one the population center. Use of distributed switching allows for the majority of calls that are local to that population center to be switched there without needing to be transported to and from the host switch. The host switch provides connectivity between the remote switches and to the larger network, and the host may also directly handle some rare and complex call types conference call ing, for example that the remote itself is not equipped to handle. Host switches also perform OAM&P Operation, Administration, Maintenance, and Provisioning functions, including billing, for the entire cluster of the host and its remote switches. A key capability of a remote switch is the ability to act in emergency standalone ESA mode, wherein local calls can still be placed even in the event that the connection between that remote and the host has been lost. In this mode, only local calling is available anyway, so the billing capability of the host switch ... router s and Ethernet switches utilize distributed switching on separate cards within an equipment chassis . Even when this is used, it is common to have a centralized switching fabric to interconnect ... more details
In computational complexity theory , H stad s switching lemma is a key tool for proving lower bounds on the size of constant depth Boolean circuits . Using the switching lemma, harvtxt H stad 1987 showed that Boolean circuits of depth k in which only AND, OR, and NOT gates are allowed require size math exp left Omega left n frac 1 k 1 right right math for computing the parity function . The switching lemma says that depth 2 circuits in which some fraction of the variables have been set randomly depend with high probability only on very few variables after the restriction. The name of the switching lemma stems from the following observation Take an arbitrary formula in conjunctive normal form , which is in particular a depth 2 circuit. Now the switching lemma guarantees that after setting some variables randomly, we end up with a Boolean function that depends only on few variables, i.e., it can be computed by a decision tree of some small depth math d math . This allows us to write the restricted function as a small formula in disjunctive normal form . A formula in conjunctive normal form hit by a random restriction of the variables can therefore be switched to a small formula in disjunctive normal form. The original proof of the switching lemma harv H stad 1987 involves an argument with conditional probabilities . Arguably simpler proofs have been subsequently given by harvtxt Razborov 1993 and harvtxt Beame 1994 . For an introduction, see Chapter 14 in harvtxt Arora Barak 2009 . References refbegin Citation last1 Arora first1 Sanjeev authorlink1 Sanjeev Arora last2 Barak first2 Boaz title Computational Complexity A Modern Approach url http www.cs.princeton.edu theory complexity publisher Cambridge University Press Cambridge year 2009 isbn 978 0 521 42426 4 author Sanjeev Arora, Boaz Barak ref harv citation last Beame first Paul title A Switching Lemma Primer journal Manuscript year 1994 ref harv citation first Johan last H stad authorlink Johan H stad title Computational ... more details
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