意大利死狗洞奥秘共25页文档

合集下载

第2节奇妙的二氧化碳

凝固液化
气态
液态
CO2的用途
灭火
尿素
纯碱
汽水
人工降雨
CO2
光合作用
工业原料
制冷剂温度计
你会设计吗？
你能根据一些事实或用实验证明二氧化碳能溶于水吗？方法一：向一个收集满二氧化碳气体的塑料汽水瓶中加入一定体积的水，立即盖紧瓶盖，振荡。
实验现象分析
塑料瓶变瘪了
瓶里压强减小，
证明二氧化碳溶于水
第2节奇妙的二氧化碳
意大利的屠狗洞
小狗为什么会死呢？
1.了解二氧化碳的物理性质和用途，初步掌握二氧化碳的化学性质。 2.了解二氧化碳在自然界碳循环中的作用以及对人类生活和生产的影响。 3.认识化合反应和分解反应的特点。 4.学会实验室制取二氧化碳的方法。
一、自然界中的二氧化碳空气中二氧化碳的体积分数是 0.03% 。
（2）可以与石灰水反应。现象：澄清石灰水变浑浊反应的文字表达式：氢氧化钙+二氧化碳→碳酸钙+水 Ca(OH)2 CO2 CaCO3 H2 O
——利用这个反应可以检验二氧化碳气体的存在
（3）不能燃烧也不支持燃烧。
现象
蜡烛火焰自下而上依次熄灭
二氧化碳不能燃烧也不支持燃烧，且密
结论
度比空气大
（4）不供给呼吸。
知识点一、二氧化碳的性质、用途及对环境的影响【典例1】下列有关二氧化碳的说法正确的是（ D ） A.二氧化碳有毒，吸入过多会使人中毒而死亡 B.二氧化碳含量的增加是造成温室效应的主要原因，因此空气中二氧化碳的含量越低越好 C.二氧化碳气体能使紫色石蕊溶液变红
D.二氧化碳能灭火是因为二氧化碳不燃烧，也不支持燃
烧，且密度比空气大

世界未解之谜

上世纪20年代，英国探险者曾经短暂进入过雅鲁藏布大峡谷，他发现了大峡谷内有一条十分壮观的瀑布。因为瀑布的周围有一道彩虹，所以他将此瀑布定名为“彩虹瀑布”。 10年后，美国人贝利再次证实了这条瀑布的存在。然而，自此之后将近70年的时间里人们再也没有找到它。
在我国云南高黎贡山的原始森林，有一个奇怪的湖叫“迷人湖”，最宽处150 米，窄处60 米，水深1.5 米。奇怪的是，如果人站在湖边高声讲话，本来晴朗明丽的湖面上空就会突然乌云密布，甚至立即下起雨来，讲话声音越高，雨就落得越大。这使众多的学者专家都陷入了困境。
贝加尔湖
• 贝加尔湖之谜
• 贝加尔湖位于俄罗斯西伯利亚的南部伊尔
库茨克州及布里亚特共和国境内，世界最大的淡水湖。人们始终不明白，贝加尔湖的湖水一点也不咸，为什么会生活着如此众多的“海洋生物”：海豹、鲨鱼、海螺、海鱼和龙虾等。随着人们对自然的不断深入，这个谜团终将会得到答案。
• 神秘的瑜珈
1935年8月，意大利籍的货轮“莱克斯”号的水手们，亲眼看到美国籍纵帆船 “拉达荷马”号被海浪渐渐吞没，他们奋不顾身地从海上救起了“拉达荷马”号溺水的水手。但5天之后，“莱克斯”号的水手却惊讶地发现，“拉达荷马”竟然漂浮在海上。这并不是幻觉，因为“莱克斯”号上的水手，连同被他们救起的 “拉达荷马”号上的水手，一同登上了“拉达荷马”号纵帆船。
在1918年，因为一道闪电使他的马受惊，Major摔下致使下半身瘫痪。 1924年，他坐在河边树下钓鱼，闪电击中那棵树，左半身瘫痪。再6年，又一道闪电击中他，全身瘫痪。他死去的4年后，一道闪电击中他的坟墓，墓碑被毁。这完全是巧合吗？
巧合
地球在其46亿年的历程中，先后捕获了4颗卫星，即4个月亮。这4个月亮恰好跟地球的4个地质年代相符合，同地球4次大变动相印证我们今天看到的月球是地球的第四颗卫星，前三颗由于在运行中离地球太近，最后都坠落了三颗月亮落地中心除印度洋以外，其他两颗硕大的月球都是在北纬30度附近，形成了三大洋

Slovenské vzory dělení slov as pro změnu

Slovenskévzory dˇe leníslov:ˇc as pro zmˇe nu?Petr SojkaMasarykova univerzita v Brnˇe,Fakulta informatikyBotanická68a,60200BrnoEmail:sojka@fi.muni.czAbstrakt:Dˇe leníslov neboli algoritmickásegmentace velkémnožinyˇr e-tˇe zc˚u nˇe jakého jazyka je problémˇc astˇe jšínežby se na prvnípohled zdálo.Pro volnˇešiˇr itelnéslovenskédˇe leníslov zatím existuje pouzeˇr ešenívy-cházejícíz deﬁnice slabiky ve slovenštinˇe,bez rozsáhlého pokrytívýjimek.Z více nežmiliónu shromáždˇe ných a rozdˇe lených slov se podaˇr ilo vyge-nerovat programem P AT G EN novévolnˇešiˇr itelnévzory,kterése s nepra-videlnostmi jazyka vyrovnávajílépe neždosud dostupnéˇr ešení.Výsledekje použitelnýnejen v distribucích T E Xu,ale i v dalších systémech jako na-pˇríklad O PEN O .Použitéa diskutovanétechniky bootstrappingu,stratiﬁkace a generovánívzor˚u jsou použitelnépˇr iˇr ešeníširokého spektradalších…segmentaˇc ních“aplikací.Klíˇc ováslova:dˇe leníslov,segmentace,P AT G EN,pˇr ebíjejícívzory,bootstrapping, stratiﬁkace1MotivaceDˇe leníslov je v jádru všech aplikacípro zpracovánítext˚u.Na kvalitˇe použitého algoritmu dˇe leníslov závisímnožstvíruˇc nípráce pˇr iˇrádkovém zlomu sazby. Stáleˇc astˇe jšíjsou aplikace,kdy kontrola zlomu se neprovádív˚u bec:databázovépublikování,dávkovézpracováníXML dat m˚uže sloužit jako pˇríklad.O to vˇe tšíje poptávka po kvalitním dˇe leníslov.Obvyklépožadavky na algoritmus dˇe leníslov jsou tyto:rychlost:pˇr i optimalizaci zlomu celého odstavce naráz je potˇr eba najít dˇe lenívšech slov v odstavci.pˇr esnost:algoritmus neoznaˇcíchybnˇešvy slov pro rozdˇe lení.úplnost:algoritmus najde všechna možnádˇe leníslov.rozšiˇr itelnost:algoritmus umožníuživatelem speciﬁkovanévýjimky–napˇrí-klad slova cizího jazyka dle pravidel dˇe lenítohoto jazyka.adaptivita:jelikožseživéjazyky vyvíjejí(nedávnáreforma pravopisu v Nˇe-mecku),je potˇr ebnénemít algoritmus…zadrátovaný“a draze optimalizo-vanýtak,že pˇr i zmˇe nˇe jazyka se musízaˇcínatúplnˇe znova.68Petr Sojkaparametrizovatelnost:algoritmus umožníjinéchovánídle charakteru použití(vúzkých sloupcích napˇríklad umožníjen dva znaky na novémˇrádku místo obvykležádaných tˇrí).minimálnípamˇe t’ovénároky:aplikace typu zalomenízpráv na displeji mobil-ního telefonu je tˇr eba navrhovat s minimálními pamˇe t’ovými,a tedy energe-tickými nároky.Základním problémem tedy je vytvoˇr it algoritmus pro zvolenýjazyk,kterýv maximálnímíˇr e splˇn uje výše uvedenépožadavky.Tentoˇc lánek popisuje pˇrístup ˇr ešenítohoto problému pro slovenštinu a krátce diskutuje výsledek ve formˇe nových vzor˚u dˇe leníslov pro slovenštinu.2Stávajícístav slovenského dˇe leníslovUživatelésázecího systému T E X používajípˇr i sazbˇe výsledky dizertaˇc nípráce[16]Knuthova studenta Franka Lianga.Liang navrhl na jazyku nezávislýpopis dˇe leníslov,kterýsplˇn uje vˇe tšinu výše uvedených požadavk˚u.Dále im-plementoval program P AT G EN[17],kterýumožˇn uje tento popis generovat ze slovníku jižrozdˇe lených slov.Brzy po rozšíˇr eníT E Xu doˇCeskoslovenska zaˇc ala být otázka dˇe leníaktuálnía vznikly prvníverze slovenských aˇc eských vzor˚u dˇe lení[14,15].Obˇe byly psány ruˇc nˇe,bez použitíprogramu P AT G EN.Ruˇc nˇe psanápravidla zachycujízákladnícharakteristiky dˇe lení,tedy napˇríklad slabiˇc nýprincip,deﬁnujíco je to slabika. U etymologického pˇrístupu k dˇe leníslov,kterýje respektován v britskéangliˇc tinˇe a standardizován nakladatelstvím Oxford Universitzy Press,však je témˇeˇr každéslovo výjimkou a proto jeˇc astˇe jšígenerovánívzor˚u ze slovníku.Vˇe tšina jazyk˚u však oba pˇrístupy kombinuje,ctíse zejména zlom našvech složených slov oproti slabiˇc nému principu.Hranice mezi cítˇe ním složeného slova dle jeho etymologie však m˚uže být diskutabilní:máme dˇe lit slabiˇc nˇe ro-zumˇc i…etymologicky“a konzervativnˇe roz-um?Pro detailnívysvˇe tleníprincipu pˇr ebíjejících vzor˚u odkazujeme na[13,pˇrí-loha H]a naˇc lánky[2,22,3].Zjednodušenˇeˇr eˇc eno,vzory speciﬁkujíkontextovápravidla,kterámezi sebou soutˇežío každou mezipísmennou pozici ve slovˇe, a urˇc ují,zda na nídˇe litˇc i ne.Pravidla speciﬁkujína základˇe r˚u znˇeširokého kontextu výjimky,výjimky z výjimek,....Vzájemnˇe se pˇr ebíjejí–m˚uže existovat nˇe kolikúrovnípriorit vynuceníˇc i potlaˇc enídˇe leníslova.Vítˇe zí…nejsilnˇe jší“pra-vidlo(s nejvyššíprioritou)pro každou pozici ve slovˇe:k pozici se m˚uže vyjádˇr it pravidlo v každéúrovni.Stávajícíverze slovenských vzor˚u dˇe leníexistuje ve verzi2.0z24.4.1992 (soubor skhyph.tex):\patterns{%samohl\’asky a1\’a1\"a1e1...%dvojice spoluhl\’asokSlovenskévzory dˇe leníslov:ˇc as pro zmˇe nu?692b1b2b1c2b1\v c2b1d2b1\v d...%6spoluhl\’asok3c4v4r4n3g4n3\v s4k4v4r4k3n3\v s4k4v4\’r4k3n%koncovka-n\’yk4\v c3n\’y.k4\v c3n\’eho.k4\v c3n\’emu.k4\v c3nom.%slovn\’e z\’aklady 5alkoholauto4rkauto4rs5b4lah5b4ledn 5b4lesk...%koncovky4b4s4\v t.8c4h.8d4z.8d4\v z.4c4ht4.4j4s4\v t.4lt.4m4p4r....%cudzie slov\’a akci3a2akv\’ari3u2m gymn\’azi3umle2u3k\’emiat2ri3u2mfkli3e2nt}Z komentáˇr˚u ve vzorech je vidˇe t,jakým zp˚u sobem vzory vznikaly.Po rozge-nerovánívzor˚u popisujících slabiku jako sekvenci pˇríslušného poˇc tu souhlásek a samohlásek se vzory autorka snažila zachytit slabiˇc névýjimky na zaˇcátku a konci slov a pˇr i dˇe lenícizích slov.Lze si ale tˇežko pˇr edstavit,že by se tímto zp˚u sobem podaˇr ilo zachytit nˇe kolik milión˚u slovních tvar˚u,kteréve slovenštinˇe existují. Našvech pˇr edpon a složených slov jsou mnohévýjimky,kteréjdou proti základ-nímu slabiˇc nému principu.Tˇe ch jsou ale tisíce,ˇc i desetitisíce,a jen s enormním úsilím by se daly vypsat všechny.Proˇc eštinu byly sepsány Hallerem[10],pro slovenštinu však patrnˇe takovýsoupis neexistuje.Na archívu CTAN lze nalézt vzory vytváˇr enéjak ruˇc nˇe výše popsaným zp˚u sobem,tak automaticky z jižrozdˇe leného slovníku slov daného jazyka.Tento postup máz hlediska požadavk˚u vytˇc ených vúvoduˇc lánku mnohévýhody oproti ruˇc nˇe vytvoˇr enéverzi.Pˇrístupy se takédajíkombinovat:k ruˇc nˇe zadanémnožinˇe základních vzor˚u se dogenerujívzory pro výjimky.Nebo naopak ex post nalezenévýjimky se dajík jižvygenerovaným vzor˚u m pˇr idat jako slova–vzory s nejvyššíprioritou(úrovní),tedy rozum jako.r8o8z9u8m..3Generovánívzor˚u ze slovníku rozdˇe lených slov Problematice generovánívzor˚u na semináˇr i S L T jižbyl vˇe novánˇc lánek[1],proto zopakujeme jen hlavníprincipy a laskavéhoˇc tenáˇr e odkážeme dále na dalšíˇc lánky vˇe novanététo a pˇríbuznéproblematice[11,25,20,21].Generováníprobíháve fázích,kterése nazývajíúrovnˇe(anglicky levels). V lichýchúrovních se generujípokrývacívzory,tedy vzory,kterédle kontextu znak˚u vynucujídˇe lení,v sudýchúrovních se dˇe lenídle kontextu zakazuje.70Petr SojkaGenerovanévzory se kumulují,a výslednéchováníurˇc uje výslednámnožina vzor˚u vygenerovanáve všechúrovních.U vˇe tšiny generovaných vzor˚u pro dˇe leníslov v užívaných jazycích staˇcíˇc tyˇr iúrovnˇe,ale pro pˇr ehlednost,ale takénedostatekˇc asu vzory optimalizovat,je v ruˇc nˇe chystaných vzorechúrovnímnohem více–souˇc asnéslovenskévzory jich majínapˇríklad osm.Technologie pˇr ebíjejících vzor˚u je natolik obecná,že jejípoužitíje možnépro vˇe tšinu segmentaˇc ních problém˚u.Jako pˇríklad m˚uže sloužit problematika segmentaceˇr etˇe zce thajských znak˚u na slova–v thajském textu nejsou slova oddˇe lena mezerami[23].4Bootstrapping a stratiﬁkaceV rámci bakaláˇr sképráce[18]se podaˇr ilo shromáždit z r˚u zných zdroj˚u1 témˇeˇr milión slovenských slov.Dnešnívýpoˇc etníkapacity umožˇn ujígenerovat vzory dˇe leníi z takto rozsáhlých slovník˚u v dobách desítek minut.ˇCasovˇe nejnároˇc nˇe jšíoperaci–rozdˇe leníslovníku slov pravidly daného jazyka–lze dˇe lat pomocípˇr edchozíverze vzor˚u a místa dˇe leníslov…pouze“zkontrolovat.Jelikožvšak i tato kontrola jeˇc asovˇe nároˇc ná,lze parametry generovánívhodnou heuristikou volit tak,že vygenerovaných vzor˚u nepokrytých slov je právˇe tolik, kolik je reálnéjich v rozumnédobˇe ruˇc nˇe zkontrolovat.To znaˇc nˇe urychluje vývoj nových vzor˚u technikou bootstrappingu.Tabulka1.Výsledky jednéiterace bootstrappingu slovenského dˇe leníze slov-níku822878slovúroveˇn dobˇr ešpatnˇe chybí#vzor˚u velikost1Bohužel výslednou množinu slov nelze volnˇešíˇr it.Volnˇe pˇrístupnýseznam slov by umožnil ještˇe mnohemﬂexibilnˇe jšívytváˇr enívariant dˇe licích vzor˚u optimalizovaných pro konkrétníprojekty.Slovenskévzory dˇe leníslov:ˇc as pro zmˇe nu?71 ještˇe v tomto stoletíjedno celéˇcísloˇc asopisu TUG BOAT.Patrnˇe z d˚u vodu zpˇe tnékompatibility nejsou tyto vzory nahrazeny kvalitnˇe jšími,byt’kompatibilita je pˇr i pˇr idánívýjimek do vzor˚u ve formátu stejnˇe porušena.Dnešnívýpoˇc etnítech-nika jižumožˇn ujeˇc etnéexperimenty a generováníopakovat s r˚u znými parame-try.Vhodnými heuristikami nastaveníprah˚u akceptace adept˚u vzor˚u v jednotli-výchúrovních generováníse lze dostat na mnohem kvalitativnˇe vyššíparametry vzor˚u,nežkterédocílil pˇr ed témˇeˇrˇc tvrtstoletím Liang.Typicky je možnéza cenu mírného zvýšenívelikosti vzor˚u docílit stoprocentního pokrytíuˇcícímnožiny, nebo naopak pˇr i zadánívelikostních omezenína velikost vzor˚u lze maximalizo-vat pokrytí.A to vše s nulovou chybovostía stejnými konstantními výpoˇc etními nároky pˇr i aplikaci vzor˚u.Jinakˇr eˇc eno,poˇc et instrukcína nalezenídˇe licíchšv˚u slova je ohraniˇc en shora konstantou,nezávisle na tom,z jak velkého slovníku vzory generujeme.Dalšítechnikou,kteráse dápˇr i generovánívzor˚u použít,je stratiﬁkace.Tato technika spoˇcíváv tom,že se snažíme minimalizovat množinu slov k uˇc ení, anižbychom ale pˇr išli o funkˇc nost vzor˚u na výjimkách.Máme-li napˇríklad slovník generovanýmorfologickým analyzátorem,tedy známe od každého slovního tvaru slovnízáklad,staˇcído slovníku slov zahrnout náhodnˇe pouze pár slovních tvar˚u od jednoho lemmatu.Dˇe leníkoncovek se zgeneralizuje,nebot’koncovkovémnožiny se neustále opakujía uˇcícíalgoritmus bude mít dostatek uˇcících pˇríklad˚u,aby se pravidelnosti dˇe leníkonc˚u slov nauˇc il.Naopak se nesmív seznamu uˇcících slov zapomenout na negace a pˇr edpony.Dˇe leníza prvníslabikou slov zaˇcínajících na na-naj-,pre-pred-apod.je nutno nahlížet jako na výjimky.5Shrnutí:ˇc as pro zmˇe nu?Bylo vytvoˇr eno nˇe kolik variant nových vzor˚u dˇe lenípro slovenštinu.Vzory jsou pro testováník dispozici ve FTP archívu CSTUGu v adresáˇr i cstug/sojka/skhyp. Po nezbytnéfázi testovánípˇr edpokládáme jejich zaˇr azenído bˇežných T E Xových distribucía projektu O PEN O a budoušíˇr eny bez omezujících licenˇc-ních podmínek.Jelikožzmˇe na vzor˚u dˇe lenípravdˇe podobnˇe zp˚u sobízmˇe nu zalomeníjižvytvoˇr ených dokument˚u,je tˇr eba být v pˇrípadˇe rozšíˇr eného požadavku na zpˇe tnou kompatibilitu obezˇr etný.Jelikožna zálohováníúplných zdroj˚u vˇc etnˇe zdroj˚u potˇr ebných na generováníformátu se obvykle zapomíná,pˇr i požadavku zpˇe tnékompatibility je tˇr eba zvážit všechna pro i proti a novévzory si tˇr eba zavést jako novýjazyk(\language)spolu se starými.Jsme pˇr esvˇe dˇc ení,žeˇc as pro zmˇe nu po více neždekádˇe používánísouˇc asných vzor˚u nastal a kvalita nových vzor˚u je dostateˇc ným argumentem pro zavedenízmˇe ny.Po téjižostatnˇe nˇe kolik let volajítakéuživateléO PEN O a dalších sázecích systém˚u, kteˇrídosud používajístarévzory dˇe lení.72Petr SojkaReference1.David Antoša Petr Sojka.Generovánívzor˚u dˇe leníslov v UNICODE.V Kasprzak aSojka[12],strany23–32.2.David Antoša Petr Sojka.Pattern Generation Revisited.V Pepping[19],strany7–17.3.David Antoša Petr Sojka.Generovánívzor˚u pomocíknihovny P AT L IB a programuOP AT G EN.Zpravodaj C S TUG,12(1):3–12,2002.4.Barbara Beeton.Hyphenation exception log.TUGboat,5(1):15,kvˇe ten1984.5.Barbara Beeton.Hyphenation exception log.TUGboat,6(3):121,listopad1985.6.Barbara Beeton.Hyphenation exception log.TUGboat,7(3):146–147,ˇríjen1986.7.Barbara Beeton.Hyphenation exception log.TUGboat,10(3):336–341,listopad1989.8.Barbara Beeton.Hyphenation exception log.TUGboat,13(4):452–457,prosinec1992.9.Pat Hall a Durgesh D Rao,editoˇr i.Proceedings of EACL2003Workshop onComputational Linguistics for South Asian Languages–Expanding Synergies with Europe,duben2003.10.JiˇríHaller.Jak se dˇe líslova.StátnípedagogickénakladatelstvíPraha,1956.11.Yannis Haralambous.A Small Tutorial on the Multilingual Features of PATGEN2.dostupnéna CTAN jako info/patgen2.tutorial,leden1994.12.Jan Kasprzak a Petr Sojka,editoˇr i.SLT2001,Brno,Czech Republic,únor2001.Konvoj.13.Donald E.Knuth.The T E Xbook,volume A of Computers and Typesetting.Addison-Wes-ley,Reading,MA,USA,1986.14.Jana Chlebíková.Ako rozdˇe lit’(slovo)ˇCeskoslovensko.Zpravodaj C S TUG,1(4):10–13,1991.dislav Lhotka.ˇCeskédˇe lenípro T E X.Zpravodaj C S TUG,1(4):10–13,1991.16.Franklin M.Liang.Word Hy-phen-a-tion by Com-put-er.PhD thesis,Department ofComputer Science,Stanford University,USA,srpen1983.17.Franklin M.Liang a Peter Breitenlohner.PAT tern GEN eration program for the T E X82hyphenator.dokumentace programu PATGEN verze2.3z distribuce web2c na CTAN, 1999.18.Ján Lieskovský.Systém pro práci se seznamy slov.Bakaláˇr skápráce,Masarykovauniverzita v Brnˇe,Fakulta informatiky,2003.19.Simon Pepping,editor.EuroT E X2001,Kerkrade,The Netherlands,záˇrí2001.NTG.20.Petr Sojka.Notes on Compound Word Hyphenation in T E X.TUGboat,16(3):290–297,1995.21.Petr Sojka.Hyphenation on Demand.TUGboat,20(3):241–247,1999.22.Petr peting Patterns for Language Engineering.V Sojka et al.[24],strany157–162.23.Petr Sojka a David Antoš.Context Sensitive Pattern Based Segmentation:A ThaiChallenge.V Hall a Rao[9].24.Petr Sojka,Ivan Kopeˇc ek,a Karel Pala,editoˇr i.Proceedings of the Third InternationalWorkshop on Text,Speech and Dialogue—TSD2000,Lecture Notes in Artiﬁcial Intelligence LNCS/LNAI1902,Brno,záˇrí2000.Springer-Verlag.25.Petr Sojka a PavelŠeveˇc ek.Hyphenation in T E X–Quo Vadis?TUGboat,16(3):280–289,1995.。

Englishpod完美打印版

Englishpod DialoguesElementary - Difficult Customer (B0001)A: Good evening. My name is Fabio, I’ll be your waiter for tonight. May I take your order?B: No, I’m still working on it. This menu is not even in English. What’s good here?A: For you sir , I would recommend spaghetti and meatballs.B: Does it come with coke and fries?A:It comes with either soup or salad and a complimentary glass of wine, Sir .B: I’ll go with the spaghetti and meatballs, salad and the wine.A: Excellent choice, your order will be ready soon.B: How soon is soon? A: Twenty minutes?B: You know what? I’ll just go grab a burger across the street.Elementary - Calling In Sick (B0002) A: Hello, Daniel speaking, how may I help you?B: Hi, Daniel, Julie here. A: Hi, Julie, how are you?B: Actually, I’m feeling quite ill today. A: I’m sorry to hear that. What’s wrong?B: I think I’m coming down with the flu. I have a headache, a sore throat a runny nose and I’m feeling slightly feverish. A: I see... so you’re calling in sick?B: Yes, I was hoping to take the day off to recover .A: OK, then. Try and get some rest. Elementary -Daily Life - Hotel Upgrade (C0003)A: Good afternoon. What can I do for you? B: I’d like to check in please. I have a reservation under the name Anthony Roberts.A: All right R.O.B.E.R.T .S... Oh, Mr . Roberts we’ve been expecting you& and here is your keycard to the presidential suite.B: But there must be some mistake; my reservation was for a standard room. A: Are you sure? Let me double check.B: Yeah&Here, this is my confirmation number .A: You’re right Mr . Roberts, there seems to be a mixup, unfortunately we’re overbooked at the moment . B: So&A: Not to worry. We’re pleased to offer you a complimentary upgrade. B: Presidential suite baby! Elementary -The Office - I need an assistant! (C0004)A: ...like I told you before, we just don’t have the resources to hire you an assistant. B: I understand that, but the fact is we’re understaffed.A: The timing is just not right. The economy is bad, and it’s too risky to take on new staff.B: Yeah, I guess you’re right.... here’s an idea, whatif we hire an intern? She would take some of the weight off my shoulders. A: She?B: Yeah, you know, a recent graduate. She could give me a hand with some of these projects and we could keep our costs down. A: That sounds reasonable... let me see what I can do.A: Tony, I’d like to introduce you to your new assistant.B: OK, great! Let’s meet her! C: Hi, I’m Adam.B: Oh... hi... I’m Tony... Elementary -Daily Life - Cut In Line (C0005)A: I can’t believe it took us two hours to get here. The traffic in New York is unbelievable. B: Yeah, but just relax honey, we’re here and we’re going on vacation. In a few hours we’ll be in Hawaii, and you’ll be on the golf course.A: Oh no!Look at that line! It must be a mile long!There’s no way I’m waiting for another two hours.B: Honey... don’t...C: Hey man, the end of the line is over there. A: Yeah...C: No seriously, I was here first, and you can’t cut in line like this. A: Says who? C: I do!A: So sue me!C: Alright...that’s it....Elementary - The Weekend - Road Trip (C0006)A: So, are we all ready to go?B: Yup, I think so. The car’s packed; we have munchies and music, and the map’s in the car .A: Did you get the camera?B: Got it! Did you fill up the tank? A: Yup, it’s all set.B: You’re sure we’re not forgetting anything? A: I’m sure... we’ve got all our bases covered.B: Well& let’s get going then! I love road trips!B: Um... do you think we can make a pit stop?A: But we’ve only been on the road for ten minutes.B: I know, but I forgot to go to the bathroom before we left.Elementary - The Office - Virus! (C0007)A: Oh great! This stupid computer froze again! Thats the third time today! Hey Samuel, can you come take a look at my PC? It’s acting up again. It must have a virus orEnglishpod Dialoguessomething.B: Just give me a second; I’ll be right up. B: I ran a virus scan on your computer , and it turns out that you have a lot of infected files!A: But I’m quite careful when I’m browsing the internet, I have no idea how I could have picked up a virus.B: Well, you have to make sure that your anti-virus software is updated regularly; yours wasn’t up to date, that’s probably what was causing your problems. A: Ok. Anything else?B: Yeah, try not to kick or hit the computer! A: Um yeah& Sorry about that. Elementary - Daily Life - What’s your name again? (C0008) A: Nick! How’s it going? B: Oh, hey...A : W h a t a r e y o u d o i n g i n t h i s neighbourhood? Do you live around here? B: Actually, my office is right around the corner .A: It was great to meet you last week at the conference. I really enjoyed our conversation about foreign investment.B: Yeah, yeah, it was really interesting. You know, I’m in a bit of a hurry, but here’s my card. We should definitely meet up again and continue our discussion.A: Sure, you still have my contact details, right?B : Y o u k n o w w h a t , t h i s i s r e a l l y embarrassing, but your name has just slipped my mind. Can you remind me?A: Sure, my name is Ana Ferris. Don’t worry about it; it happens to me all the time. I’m terrible with names too.Elementary - The Weekend - Silence please! (C0009)A: Those people in front of us are making so much noise. It’s so inconsiderate!B: Dont worry about it; it’s not such a big deal.A: Oh... I cant hear a thing! Excuse me, can you keep it down?C: Sure, sorry ’bout that!A: Someone’s phone is ringing!B: Honey, I think it’s your phone. Did you forget to switch it off?A : O h , n o ! Yo u ’r e r i g h t. T h a t ’s s o embarrassing!C: Do you mind keeping it down? I’m trying to watch a movie here!Elementary - The Office - Driving Sales (C0010)A: All right, people. We’re holding this meeting today because we’ve got to do something about our sales, and we need to do it NOW! I want concrete solutions. How do you intend to drive sales... Roger?B: Well, in fact, we’re the most expensive in the market, so maybe we need to lower ourprices to match the competitors?A: Lower our prices? Not very creative. It’ll never fly with Swan. What kind of thinking is that? Geez. Anybody else have a better plan? Natalie?C: Um, perhaps, um, a sales promotion. Maybe a two-for-one offer , or something like that!A: What? That’s the same thing. Bad idea. Really bad idea. Dammit people come on! Think! The CEO will be here any minute. D: Do we have any ideas yet?C: Yes Mr . Swan, we were kind of considering a two-for- one offer to get more competitive. D: A two-for-one promotion? Hmm. I kind of like the sound of that. It sounds like something we should consider .A: Yeah, exactly. Just what I was thinking! In fact, that’s a brilliant idea! I’m glad we thought of that. Very creative.E l e m e n t a r y ‐ D a i l y L i f e‐New Guy in Town (C0011)A: Oh, I don’t know if you heard, but someone moved into that old house down the road.B: Yeah, I know. I met the owner of the house yesterday as he was moving in. His name is Armand.A: Really? What’s he like? You have to fill me in.B: Actually, he’s a bit strange. I don’t know... I’ve got a bad feeling about him. A: Really? Why?B: Well, yesterday I brought over a housewarming gift,but Armand started acting really weird, and then he practically kicked me out! I tried to, sort of, peek into his house, but everything was so dark inside that I couldn’t really get a good look.A: Well, you’ll never guess what I saw this morning.A delivery truck pulled into his driveway, and it dropped off a long, rectangular box. It almost looked like a coffin! B: You see! Why would he... C: Hello ladies...B: Ah, Armand! You scared the heck out of me! Thisis my friend Doris.C: A pleasure to meet you...If you are not doing anything tonight, I would like to have you both for dinner .I mean...I would like to have you both over for dinner . E l e m e n t a r y ‐ D a i l y L i f e‐Cleaning the House (C0012)A: Honey, the house is such a mess! I need you to help me tidy up a bit. My boss and her husband are coming over for dinner and theEnglishpod Dialogueshouse needs to be spotless!B: I’m in the middle of something right now. I’ll bethere in a second.A: This can’t wait! I need your help now! B: Alright, alright. I’m coming.A: Ok, here’s a list of chores we need to get done. I’ll do the dishes and get all the groceries for tonight. You can sweep and mop the floors. Oh, and the furniture needs to be dusted.B: You know what, I have to pick something up at the mall, so why don’t you clean the floors and Ill go to the supermarket and get all the groceries.A: Sure that’s fine. Here is the list of all the things you need to get. Dont forget anything! And canyou pick up a bottle of wine on your way home?B: Hey, honey I’m back. Wow, the house looks really good!A: Great! Can you set the table?B: Just a sec I’m just gonna vacuum this rug real fastA: Wait! Don’t turn it on... Elementary - The Office - Out Of Control Spending (C0013)A: OK, so now the last point on our agenda. Jill, let’sgo over the profit and loss statement.B: Great. Well, the main issue here, as you can see,is that our expenses are through the roof. A: Let’s see... These numbers are off the charts!What’s going on here!B: Well, um, sir , the company expenditures on entertainment and travel are out of control. Look at these bills for example. Just this month we’ve paid over twenty thousand dollars for hotel charges!A: OK, thank you. I’ll look into it.B: The list goes on and on. Here, this is a bill for fivethousand dollars for spa treatments!A: Thank you; that will be all. I’ll take care of it.B: Look at this one sir , eight thousand dollars were spent in one night at a place called ”Wild Things”?!A: OK, I get it!! Thank you for your very thorough analysis!Elementary - I’m in Debt (B0014) A: Hello, I’m here to see Mr . Corleone. B: Right this way, sir .C: Charlie! What can I do for you?B: Mr . Corlone, I’m really sorry to trouble you, but Ineed your help.C: Anything for you, Charlie! Your father was like abrother to me.B: Well, sir , you see, this recession has hit me prettyhard; I lost my job and I’m in a lot of debt. C: I see. . . . . .B: Yeah, you know, I’ve got credit card bills, car payments, I’ve got to pay my mortgage; and on top of all that, I have to pay my son’s college tuition.C: So you’re asking for a loan.B: Well, I just thought maybe you could help me out.C: What? At a time like this? I’m broke too, you know! You’re not the only one who has been hit by the recession! I lost half my money in the stock market crash! Go on! Get outa here!Elementary - Daily Life - I’m sorry, I love you (C0015)A: Whoa, whoa, what’s going on? Watch out! B: Hey, watch where you’re going!A: Oh, no! I’m so sorry! Are you all right? B: Oh...I don’t know.A: I feel terrible, I really didn’t mean to knock you over . My tire, just exploded, and I lost control of my bike. Really, it was an accident. Please accept my apologies. B: Just let me try to stand up.SONG: Why do birds suddenly appear , every time you are near?A: Are you okay?B: Oh, wait a second, you seem really familiar , I think I know you from somewhere. A: Yeah, I think we have met somewhere before. That’s right! We met at Aaron’s place last weekend! What a coincidence! But anyway, I’m glad to see that you’re not too badly hurt, and I should probably get going. I have a nine o’clock meeting.B: Ouch! My ankle! I think it’s broken! You can’tjust leave me like this! Are you calling an ambulance?A: Nope, I’m canceling my appointment so that Ican stay here with you.SONG: Do you remember when we met? That’s the day I knew you were my pet. I wanna tell you how much I love you. Elementary - Turn left here! (B0016) A: Hurry up, get in. B: I’m in, let’s go!A: OK, make a left here. . . no wait, I meant make aright. Come on, speed up! B: Geez! What’s the rush?A: Don’t worry about it, just drive. Oh, no, the light isabout to change. . . step on it!B: Are you nuts! I’m not going to run a redEnglishpod Dialogueslight!A: Whatever . Just turn right here. . . .The freeway will be packed at this hour . . . .let’s take a side street. Go on! Get out of our way! Move, move!B: What’s your problem! Geez. Having a fit is notgoing to help!A: Here, I know a short cut....just go down here, and we’ll cut though Ashburn Heights. Let’s go, let’s go! Watch out for that lady! B: I’m going as fast as I can!A: Yes! We made it. 5:58, just before the library closes.B: You’re such a geek!E l e m e n t a r y-Here Comes the Bride (B0017)A: I can’t believe that Anthony is finally getting married!B: Yeah well it’s about time! He’s been living with hisparents for 40 years!A: Don’t be mean. Look here come the bridesmaids!Their dresses look beautiful!B: Who are those kids walking down the aisle?A: That’s the flower girl and the ring bearer . I’m pretty sure they’re the groom’s niece and nephew. Oh, they look so cute!B: I just hope the priest makes it quick. I’m starving. I hope the food’s good at the reception.A: That’s all you ever think about, food! Oh, I think the bride’s coming now! She looks gorgeous. Wait, what’s she doing? Where’s she going?B: Oh great! Does this mean that the reception is canceled?Elementary - Upper -Intermediate - Protest! (D0018)A: This is Action 5 News reporter Sarah O’Connell reporting live from Washington, D. C. where a protest has broken out. Thousands of angry citizens are protesting against the proposed bailout of the auto manufacturing industry! Sir, sir, Sarah O’Connell, Action 5 news. Can you tell us what’s happening?B: Yeah, yeah, we’re here because we feel t h i s i s a n i n j u s t i c e ! T h e f i n a n c i a l irresponsibility of big business has to stop! We’re there to show the government that we don’t like the way that they’re spending our tax dollars!A: Sir but what exactly is making everyone so angry?B: It’s an absolute outrage, Sarah, the US government wants to give 25 billion dollars of taxpayers’ money to the auto industry. These are companies that have been mismanaged and are now nearly bankrupt. A: I see. But, many supporters of the bailout argue that it could help save the jobs of millions of hardworking Americans.B: That maybe true, and I for one don’t want to see anyone lose their job, but how can these CEOs ask for a bailout when they’re making millions of dollars? And then, they have the nerve to fly to Washington in private jets! This costs hundreds of thousands of dollars! And they’re asking for money! That is just not right!A: Good point. This is Sarah O’Connell reporting live from Washington D. C., back to you, Tom.E l e m e n t a r y - T h e W e e k e n d - Christmas Chronicles I (C0019)A: I hate working on Christmas Eve! Whoa! Get a load of this guy! Come in central, I think we’ve got ourselves a situation here. B: License and registration please. Have you been drinking tonight, sir?A: I had one or two glasses of eggnog, but nothing else.B: Step out of the vehicle, please. Sir , what do you have in the back?A: Just a few Christmas gifts, ’tis the season, after all!B: Don’t take that tone with me. Do you have an invoice for these items?A: Umm...no...I make these in my workshop in the North Pole!B: You are under arrest, sir . You have the right to remain silent. You better not pout, you better not cry. Anything you say can and will be used against you. You have the right to an attorney; if you cannot afford one, the state will appointA: You can’t take me to jail! What about my sleigh? It’s Christmas Eve! I have Presents to deliver! Rudolph! Prancer! Dancer! Get help! E l e m e n t a r y-I Can See Clearly Now (B0020)A: Hello, Arthur . What seems to be the problem?B: Hey doc. Well, I think I might need glasses. I’m getting headaches, and I really struggle to see things that are far away. But I have always had 20/20 vision.A: Sounds like you may be far-sighted. OK, then, cover your left eye and read the chart in front of you.B: Mmm.. . X, E, R, 3, a question mark, and I can’t quite make out the other symbol but I think it’s the peace sign.Englishpod DialoguesA: Wow, Arthur! You’re as blind as a bat!B: Yeah, I know, my vision is really blurry at times.A: Ok then, head on over to the other room and pick out some frames while I fill out your prescription. B: Thanks doc!A: Arthur , that’s the bathroom.E l e m e n t a r y -T h e O f f i c e -What Do You Do? (C0021)A: Oh, look, there’s Veronica and her boyfriend. She’s always going on about him at the office. Oh, great, they saw us. They’re coming this way. B: Oh, man...C: Jessica! Arthur! Hi! I’d like you to meet my boyfriend Greg, he’s the V . P . of quality and safety for a top Fortune 500 food company.A: Nice to meet you. This is my husband, Arthur .B: Hey, how’s it going? D: Hello.A: Veronica talks about you all the time. I guess you must be pretty busy at work.D: Well, yeah, a V . P . position is not easy, you know! I implement policies and p r o c e d u r e s n a t i o n w i d e o f v a r i o u s departments, as well as train junior managers in FDA and EPA regulations. I also have to oversee daily opeB: Wow, yeah... that sounds exciting.D: And what about you, Arthur? What do you do for a living?B: Oh, I’m a Top Gun pilot!E l e m e n t a r y -T h e W e e k e n d - Christmas Chronicles II (C0022)A: Really, gentlemen, you can’t take me to jail! Don’t you know who I am? Kris Kringle, you know, Papa Noel, Pere Noel, Babbo Natale, sheng dan lao ren!B: Yeah, Yeah, we’ve heard that one before, haven’t we Joe?C: Yeah, last week we booked this guy who claimed to be the tooth fairy! Can you believe that?A: It’s Christmas Eve and I have all these Presents to deliver! Where is your Christmas spirit? What will happen when all the children wake up tomorrow and don’t find any gifts in their stockings?B: Sorry buddy, you were parked in a no-parking zone, you were speeding, and you have no ID!C: Besides that, even if we let you go now, your sleigh has been impounded and those reindeer were taken to the city zoo.A: What! This is unbelievable! What’s this world coming to? Christmas is ruined!C: What’s that up ahead? It looks like... elves!! Elves!! Whoa, they’re shooting candy canes! Mayday, Mayday, we are under heavy attack! We need backup!E l e m e n t a r y-Making an Appointment (B0023)A: Hello, Fairbrook Consulting, how may I help you?B: Yes, this is Julianne Horton, and I’m calling to arrange an appointment with Ms. McNealy.A: Certainly, what day were you thinking of? B: How’s Thursday? Does she have any time available then?A: Um. . . let me double check. . . unfortunately, she’s booked solid on Thursday, how does next Monday work for you?B: Actually, I’ve got something scheduled on Monday. Can she do Tuesday?A: Sure, Tuesday’s perfect. May I ask where you’recalling from?B: Sure, Merton Financial Advisors.A: Oh, actually, Tuesday’s no good. Sorry ’bout that.E l e m e n t a r y-Where should we eat? (B0024)A: Do you two have any plans for the evening?B: We were thinking of checking out a restaurant in the neigbourhood. Do you have any suggestions?A: I know this really nice Italian place. The food is fantastic, and the d ′ecor is beautiful. I’d recommend giving it a try.C: Actually, I’m not all that crazy about Italian food; I’m in the mood for something a bit lighter .A: In that case, I know a great little bistro. They make a really tasty seafood platter; the fish is outstanding.B: It sounds fantastic, but I’m allergic to seafood, so. . .A: Okay, well, let me think. . . Oh, I know this great little place. It’s just a hole in the wall, but they do the most amazing sandwiches. You gotta give them a try.C: Ella, you took me there last time I visited, and I got food poisoning, remember? Elementary -Upper -Intermediate - Planning For The Worst (D0025)A: Well, right, let’s move to our next order of business, as many of you are aware, in recent weeks there has been a lot of media coverage surrounding this bird flu issue. And it’s come to my attention that our companyEnglishpod Dialogueslacks any sort of bird flu contingency plan. B: Basically, we need to come up with a clear plan; we need to outline specific actions that our company can take to maintain critical business functions in case a pandemic strikes.A: So, what I’d like to do is: first appoint someone to look after drafting our plan; Ralph, I’d like you to head up this project. C: Sure, no problem. What issues do you want me to consider?B: Well, let’s see, there are a few points we need to be thinking about. . . first, I’ll need you to analyze our numbers and figure out what kind of financial impact an outbreak might have.A: You’ll also need to think about how we can avoid any of our employees getting infected; think of ways to reduce employee-customer contact, perhaps some IT solutions that will allow our people to work from home.C: I guess you’ll need me to forecast employee absences as well, right? And I’ll think about the impact this will have on our clients. Hey, what about vaccines? Should we be thinking about getting vaccines for our employees?A: Exactly right. So, I’ll leave this to you, and we’ll review the draft plan in two weeks. Okay, so, anyone want to order some KFC for lunch?E l e m e n t a r y-New Year Resolution (B0026)A: So, did I tell you about my New Year’s resolution? I’ve decided to go on a diet.B: And you’re going to completely transform your eating habits, right?A: Exactly! I’m going to cut out all that junk I eat; no more chips, no more soda, no more fried food.B: I’ve heard this one before.A: But this time I’m going to stick to it. I really mean it! Trust me, Carol, I’m going to be a new man in one year’s time!B: Well, I guess we’ll just have to wait and see.A: Thanks, honey, that was a great meal. I’m stuffed. Do we have any chips left? E l e m e n t a r y-Asking for Time Off (B0027)A: Mr . McKenna, do you have a second? I need to talk to you about something. B: Sure, Liv, what can I do for you?A: Well, I was just wondering. . . you see, I know I’ve used up all my vacation days this year , but my sister is getting married, and the wedding is overseas, and, well. . .B: You wanna take some time off, is thatright?A: Well, sir , I was just hoping that I might be able to take some unpaid leave this year . B: What dates are you planning on taking off? I’ll need at least two months notice, so that I can plan for your absence.A: I was thinking of taking off from September first until the thirtieth. Would you be okay with that? B: Well, I guess so.E l e m e n t a r y -D a i l y L i f e -I’m Sorry, I Love You II (C0028)A: I’m so relieved that your ankle wasn’t broken! I feel just awful about this whole thing. I wanna make it up to you. Let me take you out to dinner tonight. My treat.B: That sounds great! I’d love to! Here is my address. Pick me up at eight? A: Perfect!B: Thank you for such a lovely evening! The food was amazing, and I had a great time. A: Me too. You look so beautiful tonight! I wish this night would never end. There’s something I have to tell you... B: What is it?A: I woke up today thinking this would be just like any other ordinary day, but I was wrong. A twist of fate brought us together . I crashed into your life and you into mine, and this may sound crazy, but I’m fallingE l e m e n t a r y -A d v a n c e d - Investing in Emerging Markets (E0029) A: Dad, I’d like to borrow some money.B: Sure, Johnny, how much do you need? Five bucks?A: Come on, Dad, I need thirty thousand. I wanna get into the market. You know, I’m tired of hearing all this news about the economic downturn, the inevitable recession, people stuffing their money in their mattresses. I look at this as an opportunity. This is a chance for me to get a jump start on building my nest egg.B: I don’t know about that; with all the uncertainty in the markets right now, it would be a very unwise decision to invest. I don’t know if you’re aware son, but there has been a lot of turmoil in the markets recently. There have already been half a million layoffs in the last few months, and we have no idea how the proposed stimulus package will impact the economy. There’s just too much instability. I wouldn’t feel comfortable investing in this climate.A: But look at it this way, every challenge is an opportunity. And anyway, I’m not talking about investing in the domestic market. There are emerging markets that promise great returns. Look at China, for example;Englishpod Dialoguesthey have 1.4 billion people, half a billion of whom have recently entered the middle class. Here alone, the aggregate demand for consumer goods rePresents an amazing wealth generating opportunity.B: Come on, son, you’re looking at this too naively, the Chinese market has exhibited a great deal of instability, and their currency has been devalued by almost a whole percentage point.A: Fine, then! If that’s the way you feel, so be it. But you’re losing out on a great opportunity here. I’m going to go hit up Mum for the cash.E l e m e n t a r y -D a i l y L i f e -New Guy in Town II (C0030)A: Oh, Armand, thank you for such a thoughtful invitation! It’s really very nice of you to invite us over for dinner , don’t you think so, Ellen?B: Oh, yes of course! We’d love to come over . Can I bring anything?C: No, don’t worry about it; I’ll take care of everything. I’ll see you tonight. Come with an appetite... I know I will!B: I don’t want go over to his place for dinner! He gives me the creeps! Why on earth did you accept?A: Oh come on Ellen, it will be nice to get to know him. Besides, he’s new to the neighborhood, and it would be rude to decline his invitation.B: I guess so... You always rope me into things like this!C: Ladies! Thank you for coming! You look delicious...I mean beautiful. Please come in. A: Oh Oh Armand! You are too kind! B: How did I get myself into this... E l e m e n t a r y-Canceling an Appointment (B0031)A: Hello, Samantha speaking.B: Hi Samantha. This is Angela calling. A: Oh, hi Angela, what’s up?B: I’m just calling about our meeting today. I wonder , is it possible to reschedule our appointment in the afternoon? I have a bit of an emergency that I need to take care of. A: Let me see, it shouldn’t be too much of a problem...B: I’m really sorry, I hope it doesn’t inconvenience you too much, it’s just this thing came up, and ...A: Angela, you know what, I can’t make it to our meeting, either . Why don’t we postpone it to tomorrow afternoon at the same time? B: Sounds great. See you tomorrow.C: Angela..Angela, look up! See that lady over there who is trying on a red leather jacket? Isn’t that Samantha?B: What? No wonder she told me she couldn’t make it to the meeting, oh, no, I think she saw me...E l e m e n t a r y - D a i l y L i f e -Opening a Bank Account (C0032)A: Next, please. May I help you, sir?B: Hello, yes, I’d like to open a bank account.A: Certainly, I can can help you with that. What type of account would you like to open? A chequing or a savings account? B: What What features do they offer?A: Well, if you just take a look here, see, with our chequing account, you can have unlimited daily transactions for a small monthly fee, and our savings account has a higher interest rate, but you must carry a minimum balance of $ 10,000 dollars.B: I see, well, I think I’m more interested in a chequing account; I like to have easy access to my money.A: Alright, then, with this chequing account you’ll be issued a debit card and a cheque book. Will you require overdraft protection? There is an extra fee for that. B: No, that won’t be necessary.A: In that case, I’ll get you to fill out this paperwork; I’ll need your social insurance number , and two pieces of government ID. If you could just sign here, and here, and here; we’ll be all set. Would you like to make a deposit today?B: Yes, I’d like to deposit one billion dollars. Elementary - Foul! (B0033)A: Has the game started yet? B: Yeah, about 5 minutes ago. A: Who’s winning?B: The Bulls, of course!A: What! That wasnt a foul! C’mon, ref!B: Don’t worry, Shaq always screws up free throws.A: You were right! He didn’t make the shot! B: That was a great shot! A three pointer , yeah!A: Did you see that? He traveled and the ref didn’t call it!B: This ref needs glasses. Hey ref, open your eyes! I can’t believe he didn’t see that!A: Okay... end of the first quarter ... Alright, I’m gonna make a beer run.Elementary - Upper -Intermediate - Live from Washington (D0034)A: This is Madeline Wright, for BCC News reporting live from Washington D. C. where, very shortly, the new President will deliver his inaugural address. Just moments ago, the President was sworn-in to office; following。

二氧化碳的性质 (1)

加热
(1) 碳 + 氧气
C O2
点燃
二氧化碳
CO2
点燃
(2) 铁 + 氧气 Fe O2
(3) 红磷 + 氧气 P O2 (4) 石蜡 + 氧气
O2 点燃
四氧化三铁 Fe3O4
五氧化二磷 P2O5 二氧化碳 + 水
CO2 H2 O
1，2，3，5，6 属于化合反应
点燃
(5) 硫 + 氧气 O2 S
点燃
二氧化碳让我爱并痛着
A ×
爱的选择
C D ∨ ∨
B ？
一、二氧化碳的物理性质
1、无色无味的气体 CO2
气态升华液化
固态
CO2
凝固
CO2
液态
干冰
如果用飞机从高空撒布干冰，由于干冰升华吸热，空气中的水蒸气迅速冷凝变成水滴，于是就开始下雨了。这就是干冰用于人工降雨的奥秘。
（还有人工降雨、制冷剂、制汽水等）
光合作用
灭火
化工原料
气体肥料
1、通过刚才的学习，你现在能解释为什么雪碧、可乐都属于碳酸饮料了吗？
2、夏天我们喝过冰雪碧后，常感觉胃里胀气，还直打嗝，你能解释为什么吗？
3、长期存放的蒸馏水还纯净吗？
4、观察久置石灰水的试剂瓶瓶壁、瓶口，你发现了什么？它是怎样形成的？
二氧化碳的化学性质
1、能与水反应 CO2 + H2O → H2CO3 （能使紫色的石蕊试液变红） H2CO3→ CO2 ↑+ H2O
加热
（H2CO3不稳定，易分解） 2、不能燃烧，也不能支持燃烧 3、可与澄清的石灰水反应 CO2 + Ca(OH)2→CaCO3 + H2O

揭开“南美大隧道”之谜

揭开“南美大隧道”之谜是史前的文化奇迹吗？——“南美大隧道”之谜？这条隧道叫做Cueva de （los） Tayos，。

图片来自wiki，谷歌厄瓜多尔的南美大隧道是一个十分经典的“未解之谜”，常常被收录于各种未解之谜的丛书之中。

小时候的我对这类的包含着史前文明的探险故事欲罢不能，并且深信不疑。

但是根据书中的记载，此事已经是40年多前发生的了，此后是否进行过探索，一直牵动着我的心。

因为始终不知道这条隧道的名称，因此自然在外网上无从下手。

直到在开始考证前，不妨先看一下网络和书籍中常见的故事的“原文”：1965年，50岁的阿根廷考古学家胡安·莫里茨来到厄瓜多尔，本来准备研究一下当地的各种部族以及人种学等。

然而他在6月份的一次调查研究中，却意外地发现了一条来历不明的大隧道，莫里茨进入这条隧道勘察了数百公里，在其中发现了许多文物，莫里茨估计这条隧道通往南美大陆的地底深处，绵延约数千公里。

1969年，莫里茨请求面见厄瓜多尔总统，向他作了有关隧道的汇报。

1969年7月，胡安·莫里茨获得由厄瓜多尔国家授权并经过公证的证书，证明他拥有厄瓜多尔地下洞穴的所有权，但要受厄瓜多尔国家政府监控。

目前这条隧道只在厄瓜多尔和秘鲁境内的数百公里被人们考察和测量过，估计长度约在4000公里以上，人们尚不知道其最终向何处，现在这个隧道的入口处由一个未开化的印第安部落日夜严密把守。

1972年3月4日，由厄瓜多尔考古学家法兰士和马狄组成的科学调查小组，在莫里茨的带领下，再次对大隧道展开调查。

调查队员钻进了神秘莫测的地下世界，在隧道里，他见到了宽阔、笔直的通道和墙壁，多处精致的岩石门洞和大门，加工得平整光滑的屋顶与面积达两万多平方米的大厅，还有许多每隔一定距离就出现的平均1.8米至3.1米长、80厘米宽的通风井。

他们毫不怀疑地认为，这是我们这个世界上最大的工程，也是世界上最大的、最难破解的谜。

在这条隧道里，蕴藏着无数对人类具有重大文化和历史价值的极为珍贵的古代遗物。

黑死病劫难之谜

他们俩起来看了一看，以为这声音是梦中听到的，于是重新又躺下来。

但是，他们忽然发现他们的床已被弄到荒无人烟的旷野。

周围没有房子，没有任何建筑物，也没有牲畜。

只有一把椅子还留在他们的旁边，折叠好的衣服仍好端端地摆在上面！空中飞物是龙卷风现象中最不可思议的。

带着这些东西飞行的是龙卷风呢还是云层？1917年3月23日新奥尔尼市曾有过一次空中坠物的奇雨：在离遭龙卷风袭击的村庄40公里远的地方，从云端落下来衣物碎片、残缺不全的家具、瓦片、一扇厨房中柜子的厚门，还有一罐子渍黄瓜等。

显然，云层是不能带着这些重物在空中一起飞行的。

（圆圆摘自《自然界趣闻》）黑死病劫难之谜有一种跳蚤附在一种善于长途移居、随处栖身繁衍的家鼠毛皮间。

被带菌跳蚤咬过或沾染病人排泄物的人，都可能染病。

14世纪的欧洲人把这场疫疠，视作上帝对人类犯罪的严重惩罚。

这种令人恐惧莫名的疫疠随商旅自中亚细亚传到克里米亚，然后由往来的船只带至地中海沿岸，再肆虐整个欧洲大陆。

疫疠流行时，正常生活立刻停顿，田地荒废，牲畜乏人照管，被放掉任其自生自灭。

疾病迅速蔓延，居民逃难住所，城市面目全非。

空气也似乎充满了病菌，当年的一项记载描述说：“一种令人欲呕的恶臭弥漫……简直受不了。

”只有少数地方的居民逃过大难。

例如米兰大主教曾下令，如果疾病传播到米兰，最先发现疫疠的三所房屋，必须立即在周围建起围墙，把死者、病者和健康的人全部埋葬在内。

结果疫疠真的没有在米兰一地蔓延。

主教虽然不知疫疠怎样蔓延，但是无意中摸对了一种阻挡疫疠蔓延的有效方法：隔离。

因此，乡间孤立的房屋可能是个很好的庇护所。

意大利作家薄伽丘的《十日谈》一书，讲述10个贵族青年，为了避开侵袭佛罗伦萨的疫疠，躲进宫殿中讲故事，打发时间，等待疫疠消退。

Konrad-Zuse-Zentrum für Informationstechnik Berlin =- = = =H. Melenk H.M. Möller* W. NeunSymbolic Solution of Large Stationary ChemicalKinetics ProblemsFernuniversität HagenFB Mathematik und InformatikD-5800 HagenFederal Republic of GermanyPreprint SC 88-7 (November 1988)Herausgegeben vomKonrad-Zuse-Zentrum für Informationstechnik Berlin Heilbronner Strasse 101000 Berlin 31Verantwortlich: Dr. Klaus AndreUmschlagsatz und Druck: Verwaltungsdruckerei Berlin ISSN 0933-7911Contents1. Introduction 12. Multivariate Polynomials and Groebner Bases 43. The Computation of Groebner Bases 84. Solution of Systems of Algebraic Equations 115.C o m p u t a t i o n s for Chemical Reaction Systems 145.1 Polynomial equations 145.2 Computations with algebraic coefficients 155.3 Computations with numerical coefficients 206. Examples from Related Application Areas 25Conclusion 28 References 29AbstractThe paper presents a new application of computer algebra to the treatment of steadystates of reaction systems. The method is based on the Buchberger algorithm. Thisalgorithm was modified such that it can exploit the special structure of the equationsderived from reaction systems, so even large systems can be handled. In contrastto numerical approximation techniques, the algebraic solution gives a complete anddefinite overview of the solution space and it is even applicable when parametervalues are unknown or undetermined. The algorithm, its adaptation to the problemclass and its application to selected examples are presented.1. IntroductionUsually, chemical reaction systems for mass action kinetics are described by a set ofordinary explicit first order differential equationsCm = Yl k-+3I I C V (Vjm. - Vim) , m = 1, . . . , J V (1.1)R \l=l Jwhere c m is the (time dependent) concentration of a species a m, R is the set of allelementary reactions (reaction network), &,-_>,• is the rate constant for the elementaryreaction a t- —• a,j and has a nonnegative real constant value, and yu is the stoi-chiometric coefficient of species a; in the i th complex [9]. The yu are nonnegativeinteger constants (usually 0, 1, or 2) and so the right-hand side of (1.1) is a vectorof multivariate polynomials with variables c/.A steady state of the reaction system is a composition {c m} such that all deriva-tives c'm vanish. So the steady state is described by :0 = £ k^j ( ft cf" ) (y jm - Vim) , m = l,...,N (1.2)R M=l /This is a system of homogeneous algebraic equations and we are looking for solu-tions of (1.2) with real values C/ > 0 or c; > 0 (positive steady state).Until now solutions of such systems are nearly exclusively sought by numericalmethods. The possible advantages of an algebraic approach over the numerical treat-ment could be:a) applicability even if some or all constants are unknown (formal parameters),b) giving a complete and definite answer including the information about thedimension of the solution space (= number of solutions).FEINBERG analyzes the steady state behaviour of a chemical reaction system inthe deficiency zero and deficiency one theorems by analyzing the network structurewith graph theoretic methods. The algebraic approach allows to do a similar analysis,even in cases which these theorems do not cover.The following examples (taken from [9]) may serve as a first illustration. Theirprocessing will be discussed in part 5.c'i = aci — ßc\ — jcic2 + ec3c2 = -7C1c2 + (e + 2ö)c3-277c22 (1.3)c3 = 7C1C2 + r)c\ - (e + 6)c31Here the deficiency zero theorem states, that there is only one positive steadystate. The algebraic treatment of the homogeneous version of the above systemleads to three distinct solutions:ci = c2 = c3 = 0Cl = J , C2 =C3 = 0(1 4)a ay 9 a2 72 6So there is only one solution with positive (ci, c2, C3) and the algebraic approach inthis case confirms the deficiency zero theorem.For the second system (EDELSTEIN) the deficiency zero theorem is not applicable:c"i = a ci — ßc\ — 7CiC2 + ec3c2 = -7CiC2 + (e + 6)c3 - rjc2 (1.5)c'3 = 7C1C2 + r/c2 - (e + 0)c3This system has a one dimensional solution space; taking C\ as parameter the com-plete solution is:-^7C? + {aß - ßr))c! + arjc3 = c x(-ße + ß6)c x +ae + adc2 = d"foci — erjwhich describes c2 and c3 as functions of C\ and shows, that forer]Cl = Tethere is a pole.The kernel for the algebraic treatment of (1.2) is the Buchberger algorithm [4, 5].This algorithm transfers a system of multivariate polynomials into a Groebner basis,which gives direct information about the solutions. Although this algorithm hasa simple structure, it can achieve great complexity when executed: even for simplelooking problems the intermediate results can grow dramatically in number and size,especially if the coefficients are parameters. This effect limits the applicability of thealgorithm, even if it is performed by an efficient computer algebra system.In the case of chemical reaction systems, however, we can find results for systemswith a number of variables which usually is too large for the algorithm; additionalstructure helps to reduce the computational complexity. Particular items are:a) the low degrees of the polynomials,b) the sparse pattern of the coefficient matrix,2c) the decomposability of polynomials by factorization,d) the restriction to nonnegative real solutions.The purpose of the present paper is to introduce a variant of the Buchberger algorithm which takes advantage of the above properties.In this paper we describe the Buchberger algorithm and its modifications in detail in the first part (sections 2, 3, and 4). The expository presentation is illustrated by bivariate examples. Its purpose is to enable the reader to use the algorithm for solving of simple examples by hand or, if polynomial manipulations turn out to be complicated, by means of a minicomputer. In the second part (section 5), we give some application examples. These were computed with the Groebner package, now implemented in the computer algebra system REDUCE [10, 12].32. Multivariate Polynomials and Groebner BasesMultivariate polynomials are linear combinations of power products, i.e. of terms a?!1 * • • • * x*n with nonnegative integers i\, ... , i n .In the bivariate case n = 2 we have for instancefi{xi, £2) = x x + 2x\x2 - x2 - 7 ,andf2(x1,x2) — x\x2 — 2 .These two polynomials will be used in the following for illustrating the definitions and the Groebner basis construction. The coenicients of the multivariate polynomials (here 1, 2, — 1, —7 for f\ and 1,-2 for f2) are integers, rationals or parameter expres-sions (multivariate rational functions over the integers), or more generally elements of a field or a unique factorization domain.All power products occuring with nonzero coefficients in the power product rep-resentation of a polynomial / constitute supp(f), the support of f. This is a nonvoid set if and only if / ^ 0. We have for instancesupp(f1) ={x f,x i i f,x|,l} ,supp(f2) = {x1x2,l} .The main tool for the Groebner basis method is that the set of power products is ordered by a relation < satisfying in the bivariate case1 < x[xi, if i > 0 or j > 0 ,and for arbitrary nonnegative integers a, b, i,j, k, Ix\x{ < x\x l2 implies x?a x32+h < x$+a x2+b .Examples for such (bivariate) orderings are the lexicographical ordering1 < x a < x\ < ... < x\ < ...< x2 < X\x2 < x\x2 < ... < x\x2 <...^ Xn ^ •^l^'O ^ *^i^2 ' " " ^ •^1*^2 ^ ...and the graduated lexicographical ordering1 < xi < x2 < x\ < x\X2 <x\<x\< ... .4The multivariate analogy of the lexicographical and the graduated lexicographicalordering are (<i ex for short):x\ ' ' 'x^lex x i ' ' 'x n •*' ''n3i <n : (a,- < b{ A V7 > i : aj = fcj)and (<ff;ea: for short)::> ^X l '"'X n "^glex x l ' ' 'xn\t=i t=i / \t=i t=i / Using such an ordering, the elements in a support can be ordered; and two poly-nomials / and g can be compared by saying that / is simpler than g if supp(f) andsupp(g) are different and supp(g) contains a power product which is greater ( w.r.t.< ) than every power product in supp(f) \ supp(g). Both in the lexicographical andthe graduated lexicographical ordering, f2 is simpler than /l5 because Xix\ is greaterthan XiX2, the maximal (and only) power product in supp(f2)\supp(f1). In this wayany two polynomials with different supports can be compared, but no two ones withsame support.Polynomials can be simplified with respect (to the given ordering < and) toa finite set G of nonzero polynomials. Denoting by /£(/) the maximal power productin supp(f) for / ^ 0, we say / reduces modulo G to /*, briefly / —>a f*, if a powerproduct x"1 • • • x£n of supp(f) is a multiple of a lt(g) with g 6 G andT a i . . . f a nf=C l/_C2 lt(g) 9>where the constants c1? c2 are chosen such that supp(f*) does not contain x"1 • • • x£n.All power products in supp(f*) greater than xj1 • • • x°n are identical with those insupp(f), but Xj1 • • • x£n is contained only in supp{f). Therefore, /* is simpler than /.This reduction procedure modulo G can be applied iteratively until a polynomial isobtained, which is no more reducible modulo G. (It is easy to show, cf. the survey by BUCHBERGER [5] for the case of polynomials over a field, that every iterated applica-tion of a reduction modulo a finite polynomial set G terminates after a finite numberof steps at an irreducible polynomial or at the zero polynomial.) We abbreviate by/—>Q /* the sequence/ —>G 9\—>G • • •—>G g3 =/*,if /* is 0 or no more reducible modulo G. If / is already irreducible modulo G or if/ = 0, then we write for short also / —>Q f.Let for instance G := {/2} and / := /i. Thenf = Xj + 2xjx2 — x2 — 7 —*a x i + 3x2 — 7 = /i — 2x2/2 =: /*5with supp(f*) = {x\,x\,l} and supp(f) = {xiX^x^Xj, 1} and hence /* is simpler than /. /* is irreducible modulo G, because supp(f) contains no power product, which is a multiple of an lt(g),g 6 G. Therefore, we may also write/ —>G r •When the common zeros of a finite set of polynomials H = {/i1; ... , h s} have to be computed, everysh = ]T g{hi, with polynomials g u ... , g st=ivanishes at these common zeros, and conversely the set of all such h's1(H) := I ]T g{hi | g u ... , g s polynomials \has the same set of common zeros like H, because H is a subset of it. 1(H) is called the ideal generated by H. Therefore, for computing the common zeros of H, another finite set of polynomials generating 1(H), a so-called basis of 1(H), can be taken in place of H. We are dealing with Noetherian rings, where all ideals are generated by a finite subset. Therefore we may speak of an ideal instead of an ideal generated by a finite polynomial set H, if H is of no relevance for the forthcoming.Definition. A finite set G of nonzero polynomials is called a Groebner basis of an ideal I, if for arbitrary / £ I/—*G0-R e m a r k 1. A Groebner basis of an ideal generates in fact the ideal. The Groebner bases depend on the given ideal and also on the given ordering of the power products. But even if ideal and ordering are fixed, the Groebner basis is not unique. We obtain a uniquely determined Groebner basis, if we replace every polynomial g of a Groebner basis G by the (modulo G \ {g}) irreducible g*, g —*h\{g\ 9* an<^ ^w e normalize the coefficient belonging to lt(g*) to 1 in case the coefficient domain is a field, cf. [5], or to another special element for other coefficient domains.Remark 2. If G is a Groebner basis of an ideal I with respect to <i ex, then every polynomial f € I depending only on x1} ... , x,- is already reducible to 0 modulo the polynomials in G which depend also only on xi, ... , x,-, because the other polynomials in G have /i-parts which are multiples of an Xj, j > i and hence these It do not divide a power product in supp(f). Thus, the ideal of all polynomials in J depending only on xi, ... , x,- has the set of all polynomials in G depending only on xi, ... , x,- for Groebner basis, i = 1, ... , n — 1.6This is useful for rinding the common zeros of the polynomials in I. First the polynomials in G depending only on i j are considered. Their common zeros de-termine all possible first components for the required zeros. Then substituting the first component in all polynomials in G depending only on xi, x2 we get a univariate problem for determining all possible second components, etc.E x a m p l e. For finding the common zeros of the polynomials fi,f2 as introduced above, we consider the ideal I generated by {fi,f2}- As seen before,/3 := xl + 3xl-7 = fr- 2x22f2belongs to I. But also/4 := x1f3 - 3x2/2 = x\ - 7x x + 6x2and/5 := Z1/4 - 6/2 = x\- 7x1 + 12are in I. We will see, that {/4, f$} constitute a Groebner basis of I, when we consider all polynomials as polynomials with rational coefficients. The common zeros of /x, f2 can be easily detected by considering /4 and f5. The roots of f5 , {2, —2,\/3, —s/3} are the first components of all possible zeros in common to fi and f2. Inserting these roots into /4 = 0, we get for each choice of X\ one choice of x2:(2,1),(-2,-1), (x/3, |V3),(-x/3, -|V s)are the common zeros of /j and f2.73. T h e Computation of Groebner BasesFor the construction of Groebner bases, the notion of S-polynomials is essential. For every two nonzero polynomials /, g the S-polynomial is denned byc*lcm{lt(f),lt(g)} c*lcm{lt(f),lt(g)}ex * lt(f) c 2 * lt{g)where c x and c 2 denote the coefEents of lt(f) and lt(g) in the respective power product representation of / and g and where c := Zcm{ci,c 2}. Then the following characterization of Groebner bases for polynomials over fields [5] and over principal ideal rings [19] allows a construction of such bases.Theorem 1: A finite set of nonzero polynomials H = {hi, ... , h T } is a Groebner basis of 1(H), if and only if S(/ij, hj) —>*H 0 holds for every hi, hj 6 H.Using this theorem, we can show, that the set {/4,/s} of the example is in fact a Groebner basis. We show first, that H := {/i, • • •, /s} is a Groebner basis. This holds if S(fi, fj) —>*H 0 for i < j because the remaining S-polynomial reductions are trivial (5(/j,/,-) = 0) or follow by symmetry (S(f ii f i ) = -5(/,-,/,•)).We have /3 = 5(/i ,/2). HenceS(fi,f 2)-^HS(fi,f 2)-f 3 = 0.SimilarlyS (/2,/s )—>J j S (/2,/8) + /4 = 0andSfaf*) —*H S(f a ,f 4)- f B = 0 .More computation is required for the reduction of 5(/3, f^):S(f3, A) = 2/3 - X2/4 = —x\x 2 + lx x x<i + 2x\ - 14 =: pi•tf Pi + \xlf 4 = 711x2 + !*i - \x\ + 2x\ - 14 = *H P2-\xif A = I x 6_7x 4+S.a .2_14 >H P 3-H /5 = -}** + ¥*?-14>H P 4+|/5 = 0. P2P3P4The remaining tests S(fi,fj) —>*H 0 for i < j are as hard as the test of 5(/3, /4) —>*H 0. We omit these technicalities. (The criteria quoted in the following will show, that these remaining tests are in fact superfluous.)Therefore, H = {/1, ... , f$} is a Groebner basis. Using /3 = S(fi,f 2) and the definition of S(fi,f 2), we get /1 = /3 -f 2x\f 2. Hence each reduction step using f x for reduction can be replaced by a reduction step using /3 followed by a reduction step 8using /2. Hence/j is redundant in H, i.e. {f2,fz,f4, fs} is also a Groebner basis of the ideal 1(H). By the same argument, using /2 = \xif A +|/5, f2 is redundant in {/2, fz, IA-, fs}- And using the reduction of S(/3, f4) to 0, we find the redundancy ofh in {/3,/4,/s}- Thus {/4,/s} is a Groebner basis.The test of a polynomial set for Groebner basis will be simpler, if not all £(/,-, /_,-) with i < j have to be tested for being reducible to 0. BUCHBERGER [4] developed criteria for predicting that an S-polynomial reduces to 0. These criteria have been generalized by himself and by other authors.Definition. Let H be a set of nonzero polynomials, H := {/l5 ... , /r} . Using the notation T(/,-,/j) for lcm{lt(fi),lt(fj)} and T(/,) for lt(fi), we saya) Criterion D holds for (/,-, /s), if /,• and f s have a common (eventually constant)divisor g, such that /,• = g * /*, f s — g * f* and lt(f*), lt(f*) without common divisor.b) Criterion M holds for (fi,f s), if a j < s exists, such that T(fj,f s) dividesc) Criterion F holds for (/,-, f s), if a j < i exists, such that T(fj, f s) = T(/,-, /s).d) Criterion B s holds for (/,-,/,-), if s >j, f3 € H and T(f s) divides T(/j,/j), butTVufJtTUuMtTifjJ.).If one of the criteria M, F, and B s holds for (/,-, fj), then the S-polynomial 5(/,-, fj) reduces to 0, as shown in [11]. Criterion D is an easy generalization of Buchberger's criterion 2 [5].These criteria simplify the Groebner basis computation. In our example, only theS-polynomials S(f1,f2) = /3, S(f2, /s) = ~h, S(f2, /4) = fs, and S(/3, /4) have to be computed and reduced. For criterion M holds for (/x,/3), (/x, f4), (/i,/5), and (/3,/5),F for (/2,/s) and D for (/4,/s). The example indicates the way, in which Groebner bases can be computed. The idea for this computation is due to BUCHBERGER [4]. Using the criteria and using, that a polynomial fk is redundant in the final Groebner basis G, if an /; €G exists such that /<(/,•) divides lt(fk) and using that in this case every (fk, fj) for j > k satisfies criterion M or a slightly modified criterion F allowing the cancellation of all such (fk,fj), provided the input polynomials are ordered by^(/i) ^ ^(h) — • • • ' *n e algorithm for computing Groebner bases can be formulated in the following way.Buchberger Algorithm.Input: nonzero polynomials/1, ... , f r ordered ,such that U(f-i) >...> U(fr).Output: A Groebner G basis for I(f\, • • •, f r) .Initialization:G:=0;P:=0;9For s = 1 to r doP I := usecritMFD( {(/,/,) | for all / € G});P := join(Pl, usecritB(P,/,));G := update(/s,G);s := r ;Iteration:Let (/,-,/,)G P;P:=-P\{(/»/i)};L e t S^,/,-) —•Jjfc;If Ä ^ 0 thens := s + 1;/s := h;P I := usecritMFD( {(/,/,) | for all / € G});P := join(Pl, usecritB(P,/,));G := update(/s, G);If P 7^ 0 then goto iterationelse return GThe subalgorithm usecritMFD applies the criteria M, F, and D to a set P i of polynomial pairs (fi,f s) with fixed s and some i < s by comparing the elements of P i against each other. It returns the subset of P i consisting of all elements for which neither M nor F nor D holds true. usecritB applied to a set of polynomial pairs P and a polynomial f s cancels all pairs in P, for which criterion B a holds true. update(/s,G) cancels every polynomial g € G, for which lt(f) divides lf(g), and returns this reduced set after enlarging it by f s.The correctness and the termination of the algorithm in the present form are shown in [11], when the polynomial coefficients are elements of a field like the field of rational numbers. For other coefficient domains see [19].For simple examples, this algorithm can be applied successfully by hand calcu-lation as our example showed. For more complicated cases the use of a Computer Algebra System is recommended. Apart from the bivariate and the trivariate case, bounds for the complexity of the algorithm are in general unknown. Examples sug-gest, that these bounds will be huge, if the input polynomials or the ordering of the power products are badly chosen. We developed some special tools for constructing Groebner bases in order to solve also problems, which cannot be solved by other Computer Algebra Systems [18]. For the problem of finding the common zeros of a given set of polynomials, we installed a variant of the algorithm, which will be presented in the following.104. Solution of Systems of Algebraic EquationsWe look for the solutions of a system of algebraic equations/i(xi, ... , x n) = 0 , ... , /r(x i, ... , x n) = 0. (4.1) Let us denote the solutions of this system by Z(/i, ... , /r). Then Z(fi, ...,/,.) isthe set of common zeros of /1} ... , f r, or as already mentioned in Section 2, theset of vcommon zeros of any basis of the Ideal I generated by /l5 ... , f r. So wetransform (4.1) into a Groebner basis with lexicographical ordering g x, ... , g n and(4.1) is equivalent to gi = 0, ... , g n = 0. On the other hand a lexicographicalGroebner basis has a full or partial triangular dependency pattern, in the best casen = m and01(31»•Z-2) . . . , X n_j, X n)#2(zi, x2, ..• , x (i)9{m-l}(Xi, X2)This triagonal pattern can be exploited for the solution of (4.1), e.g. finding theroots of the last equation, substituting it into the others and so on.But the calculation of the Groebner basis in lexicographical ordering can be ex-tremely hard. So we have modified the Buchberger algorithm for the purpose ofequation solving, such that it decomposes the problem wherever possible.The algorithm (3) started with the set of polynomials G^{fi, ... , /r} generatesin iteration step n a new set G<w>. If in one of these G^%> there is a polynomial p witha decompositionp(xi, ... , x n) = 0 <£=}> (q n(xi, ... , x n) = 0 A g12(xi, ... , x n) = 0 A ...)V 92i(xi, ... , x n) = 0 A 922(^1, ... , x…) = 0 A ...)V gfci(xi, ... , x n) = 0 A 9fc2(xi, ... , x n) = 0 A ...))where the g,j are "simpler" than p, then each of the righthand alternatives representsone (possible empty) part of the complete sets of solutions. By substituting theminto G^ one after the other, we get k calculation branches and so a decompositionof the complete calculation. The effect is twofold,a) the algorithm becomes less complicated: the polynomials are often less in de-gree;11b) the final result is partitioned too, in the best case into individual solutions. There are two sources for decomposition: factorization and arithmetic restrictions. Factorization. If we find in the ideal / a polynomial ft, which can be factorized intoft = hi * • • • * h m,then Z(f u ... , f r) splits into the sets Z(f x, ..., f r, hi), ... , Z(f u ... , f r, h m).This splitting method can be combined with the algorithm for Groebner basis computation. For the computation of Z(fi,...,f T) a Groebner basis of I :=J(/i, ... , f r) can be used. Each polynomial ft, obtained by reducing an S-polynomial belongs to I. Therefore if such h is factorizable, h = hi * • • • * h m, then the Groebner basis computation for I can be stopped and the Groebner basis computations with input /1? ... , f r,hk, k = 1, ... , m, can be started, because the union of the sets Z(f\, ... , f r, hk), k =1... , m is the required set of solutions. A consequent application of this factorization gives a tree of Groebner basis compu-tations. Whenever a factorizable polynomial h is found, the computation branches into several Groebner basis computations, and the old Groebner basis computa-tion is discarded. However, the initial Groebner basis calculations for the ideals I k := I(/i, ... , /r, h/,), k = 1, ... , m, are identical with those for the ideal I, until the factored polynomial h appears. Then the algorithms usually differ. This is used in our installation of the procedure. We substitute in the algorithm for computing a Groebner basis of / the factorizable polynomial h by the respective factor hk and obtain the identical beginnings of the Groebner basis calculations for the ideals I*. (Some additional calculations may be in parallel too. Therefore before branching the algorithm, we perform also S-polynomial reductions which are known to be identical for all Groebner basis computations with respect to Ji, ... , I m.)For avoiding a multiple computation of the same zeros, we use in our installation a practical criterion. When a Groebner basis for finding Z(fi, ... , /r) is computed and a factorization of a reduced S-polynomial h, h = hi * • • • * h m, is found, then the Groebner basis calculation for finding Z(fi, ... , f r, hk) can be discarded, if a previ-ous hi,i < k, is detected in the ideal generated by /1: ... , /r, hk, because then the set Z(fi, ..., f T, h k) = Z(f u ... , f r, h k, hi) is contained in Z{f x, ... , f T, ft,-)- The same argument holds, if after forthcoming branchings a Groebner basis for a subset of Z(fi, ... , f T,hk) is computed and its corresponding ideal contains ft,-, because then this subset of Z(/i, ... , f T, hk) is contained in Z(/i, ..., f r, ft,).The algorithm for computing Groebner bases is fast, when low degree polynomial are found early in the algorithm. This is forced by the method of factorizing. We decrease 'artificially' the degrees of the reduced S-polynomials by substituting the true reduced S-polynomial by each of its factors. The increased number of simpler Groebner basis computations does not destroy this effect. On the contrary, the more factorizations are found, the faster the branching method is, as our examples show.12Only if no or if very few factorizations of polynomials h are found, then by the overhead of testing polynomials for divisibility this branching method is slower than the algorithm presented in section 3.Arithmetic restrictions. A second source for decomposition is the restriction, that only nonnegative real values make sense as components of solutions. So we can exploit a set of inequalitiesXi > 0 i = 1, ... , T V.In generalizing Descartes rule of sign we can state for a multivariate polynomialp = a0 +0l x*n•••<" + ••• + a m x[ml • • • x™nwhere all a,- are real and have the same sign:a) if ÜQ ^ 0 then p(x\, ... , x n) = 0 implies that at least one a;,- < 0;b) for a0 = 0 then p(xi, ... , x n) = 0 and £,• > 0 implies, that each monomial inp is zero already.In other words: If ao ^ 0 there cannot exist a solution which satisfies the above inequalities and the calculation branch can be cancelled. For a0 = 0 p is decomposed into a list of monomials each of which has to be zero. As these monomials are factorizable immediately, we easily get a twofold decomposition. For example, the polynomial17xy2r + Ax2zleads to the decompositionx = 0 V (y = 0 A z = 0) V (r = 0 A 2 = 0)which describes the nonnegative real solutions.Experience has shown, that in the chemical application area the above criterion plays an important role as source of decomposition and as test for the nonexistence of a relevant solution. In the last case a calculation branch can be cancelled immediately.The arithmetic decomposition uses the same hook in the algorithm as the factor-ization: when it hits, it generates sets of zero polynomials each of which is root of a separate calculation tree.If the coefficients contain formal parameters, the same technique can be applied for determining their sign.135. Computations for Chemical Reaction Systems5.1 Polynomial equationsChemical reaction systems for isothermal reactors are described by reaction networksor by systems of chemical reaction equations:ki-*j '• J/«n c n T • • • "T yim c m=*• VjkCk + ••• + VjiQ (5.1)where c s denotes the overall molecular concentration of the species with numbers,y s j is the stoichiometric coefficient of species 5 in the complex j and fc;_>j is therate constant for the reaction from complex i to j. For the numerical simulationof their kinetics they are transformed into systems of ordinary differential equations(ODEs), which in the case of mass action have the general formc3 = X^.^j I I c T\y°i - Vsi) > s = l, ... ,n . (5.2)»"—»j1=1, nThe transformation from (5.1) (or other equivalent input forms) to (5.2) can bedone automatically with REDUCE: the right-hand sides of the ODEs are initializedwith zeros and the contributions of each reaction read into the species are added intothe corresponding ODE:LET p = k^j * c n * *y in * ... * c mt- * *y im ; (5.3) FOR EACH c p in left side of (5.1) subtract (J b< * y ip) from ODE (c p) ; (5.4)FOR EACH c p in right side of (5.1) add (fc,- * y ip) to ODE (c p) ; (5.5) If we now are interested in the steady states of sytem (5.2), we have to set c s tozero. (5.2) is transformed into a system of homogeneous algebraic equations0 = $>w j I I c?'(ys: ~ Vsi) , 5 = 1, ...,n (5.6)t'->j 1=1, nwhich can be investigated with algebraic methods. The "variables" in (5.6) are thec;. The y f- are small nonnegative integer constants (typically 0,1 or 2). The fc,_j maybe numerical constants (nonnegative numbers, typically floating point fractions) orthey may be formal parameters (all or some of them). In all cases we are interestedto solve (5.6) or to look for criteria for the solvability.14。

1、洞穴奇案

其他意见概述
斯普林汉姆法官认为，紧急避难抗辩内在的法
律原则是，由于紧急避难而实施犯罪的人没有犯罪意图，所以不应该受到惩罚。如果探险者们出于紧急避难而杀人，那么他们就没有犯罪意图，或者说没有在实质的意义上故意杀了人，因此该被判无罪。（身处困境不是被困者之过错；食物匮乏并非疏忽大意造成；惩罚被告有悖于法律之目的：无需对被告人采取改造措施，因为他并没有表露出某种邪恶人格。）
4299年5月上旬，在纽卡斯国，五名洞穴探险人不幸
遇到塌方，受困山洞，等待外部的救援。十多日后，他们通过携带的无线电与外界取得联络，得知尚需数日才能获救，但水尽粮绝，为了生存，大家约定通过投骰子吃掉一人，牺牲一个以救活其余四人。威特摩尔是这一方案的提议人，不过投骰子之前又收回了意见，其他四人却执意坚持，结果恰好是威特摩尔被选中，在受困的第23天威特摩尔被同伴杀掉吃了。在受困的第32天，剩下四人被救，随后他们以故意杀人罪被起诉，而根据《刑法典》规定：“任何故意剥夺他人生命的人都必须被判处死刑。
案情中的细节
1.探险者进入山洞前留下了字条，如果超过预定时间
没有回营地就意味着需要援救。 2.营救过程中，10名营救人员因山崩丧命，近百万元的资金投入救援。 3.在被困的第20天，营救人员获知探险者随身
携带了一个袖珍无线设备，可以收发资讯。联系上探险者们后，营救人员告知他们至少需要 10天他们才能获救。受困的探险者们与营救医生通了电话，详细描述了洞里的情况，然后问从医学上看，在没有食物的情况下，他们是否有可能再活10天。医生告诉他们：这种可能性微乎其微。随后，洞内的无线电设备便沉寂了。
首席法官伯纳姆陈词：撇开己见
8.守护法律是法官的职责。我们给予公民的是一张选

10个深藏地窖的秘密

10个深藏地窖的秘密10个深藏地窖的秘密地窖里不只留存着人类的尸骨。

这些深藏地下的葬身之地还保留着秘密。

在地窖中，我们发现了艺术杰作、遗迹甚至关于疾病的证据。

这些神秘的作品吊足了考古学家的胃口，通过这扇窗户，他们可以了解亡者的世界。

而地窖中还有更多谜题等待我们去揭开。

10.西伯利亚人的尸体面模2015年，研究人员在西伯利亚克麦罗沃（Kemerovo）地区的一座古老地窖内发现了20个尸体面模。

这座陵墓属于神秘的塔施提克人，他们曾于公元前300年到公元500年之间控制着西伯利亚的大部分地区。

这座墓室深埋地下，四周是石墙，顶上覆盖着木质屋顶。

研究人员花了两年时间才挖掘出这座庞大的墓坑。

考古学家发现了30具经过火葬的遗骸，装在布和皮革制成的假体中。

假体的面部是由石膏制作而成的“尸体面模”。

令人惊讶的是，塔施提克人的尸体面模在外形上具有欧洲人的特征。

陵墓外还发现了儿童的遗骸。

所有青少年都没有戴面模。

石膏是一种柔软的矿物质，因此很多面具都已破碎。

但是，专家认为这些破碎的面具可以被重新拼凑起来。

9.7具神秘的干尸2009年，考古学家在一座有900年历史的地窖中发现了七具干尸，地窖的墙壁上还刻满了神秘碑文。

这些自然保存下来的遗骸来自古栋古拉（Dongola）的一座修道院深处，栋古拉是中世纪时马库里亚（Makuria）——位于今天的苏丹——的首府。

这座地窖内存放了七具遗骨，死亡时的年龄都在40岁以上。

墓室由砖块和泥灰浆密封。

地窖白色的墙壁上用黑墨水写满了埃及古语和希腊语的碑文。

还有福音书的节选以及神秘的名字与符号，有人认为这是为了保护死者免遭邪恶力量的侵袭。

传说刚刚去世的人会处在不稳定的状态中，在灵魂受审之前很容易受到侵害。

这座地窖最早于1933年被发现，但是直到70多年后才开始挖掘。

专家认为其中一具干尸是总主教乔治斯（Archbishop Georgios），他是马库里亚最有权势的基督徒。

8.佛陀的头盖骨考古学家认为，他们可能在中国南京报恩寺地窖内一只有千年历史的箱子里发现了一片佛陀的头盖骨。