|
问题：TheabacuswasTheabacuswasinventedinthesixthcenturybythechinese写篇作文,初三第九单元的SELFCHECK的那篇,求高手写篇,
答案：↓↓↓ 陈克非的回答： 网友采纳 Anabacus,alsocalledacountingframe,isacalculatingtoolusedprimarilyinpartsofAsiaforperformingarithmeticprocesses.Today,abaciareoftenconstructedasabambooframewithbeadsslidingonwires,butoriginallytheywerebeansorstonesmovedingroovesinsandorontabletsofwood,stone,ormetal.Theabacuswasinusecenturiesbeforetheadoptionofthewrittenmodernnumeralsystemandisstillwidelyusedbymerchants,tradersandclerksinAsia,Japan,Africa,Indiaandelsewhere. Theuserofanabacusiscalledanabacist;heorsheslidesthebeadsoftheabacusbyhand.[1] TheearliestknownwrittendocumentationoftheChineseabacusdatestothe14thcenturyAD.[13] Thetopoftheabacusiscalledtheheavenandthebottomiscalledtheearth.[14] TheChineseabacusknownasthesuànpánistypically20cmtallanditcomesinvariouswidthsdependingontheoperator.Itusuallyhasmorethansevenrods.Therearetwobeadsoneachrodintheupperdeckandfivebeadseachinthebottomforbothdecimalandhexadecimalcomputation.Modernabacuseshaveonebeadonthetopdeckandfourbeadsonthebottomdeck.Thebeadsareusuallyroundedandmadeofahardwood.Thebeadsarecountedbymovingthemupordowntowardsthebeam.Ifyoumovethemtowardthebeam,youcounttheirvalue.Ifyoumoveaway,youdon'tcounttheirvalue.[citationneeded]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. | 
