TheabacuswasTheabacuswasinventedinthesixthcenturybythechinese写篇作文,初三第九单元的SELFCHECK的那篇,求高手写篇,
<p>问题：TheabacuswasTheabacuswasinventedinthesixthcenturybythechinese写篇作文,初三第九单元的SELFCHECK的那篇,求高手写篇,<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">陈克非的回答：<div class="content-b">网友采纳 Anabacus,alsocalledacountingframe,isacalculatingtoolusedprimarilyinpartsofAsiaforperformingarithmeticprocesses.Today,abaciareoftenconstructedasabambooframewithbeadsslidingonwires,butoriginallytheywerebeansorstonesmovedingroovesinsandorontabletsofwood,stone,ormetal.Theabacuswasinusecenturiesbeforetheadoptionofthewrittenmodernnumeralsystemandisstillwidelyusedbymerchants,tradersandclerksinAsia,Japan,Africa,Indiaandelsewhere. Theuserofanabacusiscalledanabacist;heorsheslidesthebeadsoftheabacusbyhand. TheearliestknownwrittendocumentationoftheChineseabacusdatestothe14thcenturyAD. Thetopoftheabacusiscalledtheheavenandthebottomiscalledtheearth. TheChineseabacusknownasthesuànpánistypically20cmtallanditcomesinvariouswidthsdependingontheoperator.Itusuallyhasmorethansevenrods.Therearetwobeadsoneachrodintheupperdeckandfivebeadseachinthebottomforbothdecimalandhexadecimalcomputation.Modernabacuseshaveonebeadonthetopdeckandfourbeadsonthebottomdeck.Thebeadsareusuallyroundedandmadeofahardwood.Thebeadsarecountedbymovingthemupordowntowardsthebeam.Ifyoumovethemtowardthebeam,youcounttheirvalue.Ifyoumoveaway,youdon'tcounttheirvalue.Thesuanpancanberesettothestartingpositioninstantlybyaquickjerkalongthehorizontalaxistospinallthebeadsawayfromthehorizontalbeamatthecenter. Suanpanscanbeusedforfunctionsotherthancounting.Unlikethesimplecountingboardusedinelementaryschools,veryefficientsuanpantechniqueshavebeendevelopedtodomultiplication,division,addition,subtraction,squarerootandcuberootoperationsathighspeed. InthefamouslongscrollAlongtheRiverDuringtheQingmingFestivalpaintedbyZhangZeduan(1085–1145AD)duringtheSongDynasty(960–1297AD),asuanpanisclearlyseenlyingbesideanaccountbookanddoctor'sprescriptionsonthecounterofanapothecary's(Feibao). ThesimilarityoftheRomanabacustotheChineseonesuggeststhatonecouldhaveinspiredtheother,asthereissomeevidenceofatraderelationshipbetweentheRomanEmpireandChina.However,nodirectconnectioncanbedemonstrated,andthesimilarityoftheabacimaybecoincidental,bothultimatelyarisingfromcountingwithfivefingersperhand.WheretheRomanmodel(likemostmodernJapanese)has4plus1beadperdecimalplace,thestandardsuanpanhas5plus2,allowingusewithahexadecimalnumeralsystem.InsteadofrunningonwiresasintheChineseandJapanesemodels,thebeadsofRomanmodelruningrooves,presumablymakingarithmeticcalculationsmuchslower. AnotherpossiblesourceofthesuanpanisChinesecountingrods,whichoperatedwithadecimalsystembutlackedtheconceptofzeroasaplaceholder.ThezerowasprobablyintroducedtotheChineseintheTangDynasty(618-907AD)whentravelintheIndianOceanandtheMiddleEastwouldhaveprovideddirectcontactwithIndia,allowingthemtoacquiretheconceptofzeroandthedecimalpointfromIndianmerchantsandmathematicians.
页:
[1]