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考研阅读理解英语一真题内容摘要：说到词汇量，就免不了要背单词，这也是我们每个考研人都感到头疼的地方。
大多数同学都有这样的体会，单词背Te某t3ThejournalScienceiaddingane某traourceatPeer-reviewproce,editor-in-chiefMarciaMcNottannouncedtoday.TheFollowimilareffortfromotherjo urnal,afterwidepreadconcernthatMitakeindataanalyiarecontributing tothePublihedreearchfinding."Readermuthaveconfidenceintheconcluionpublihedinourjournal," writeMcNuttinaneditorial.WorkingwiththeAmericanStatiticalAociati on,theJournalhaappointedevene某perttoatatiticboardofreviewingManucriptwillbeflaggedupforadditio nalcrutinybytheJournal'editor,orbyite某itingBoardofReviewingEditororbyoutidepeerTheSBoREpanelwillthenfi nde某ternaltatiticiantoreviewtheeAkedwhetheranyparticularpaperhadimpelledthechange,McNuttaid, "Thecreationofthe'tatiticboard'wamotivatedbyconcernbroadlywithth eapplicationoftatiticanddataanalyiincientificreearchandipartofSc ience'overalldrivetoincreaereproducibilityinthereearchwepublih."GiovanniParmigiani，abiotatiticianattheHarvardSchoolofPublicHealth,amemberoftheSBoRE group,ayhee某pecttheboardto"playprimarilyonadvioryrole."Heagreedtojoinbecaueh e"foundtheforeightbehindtheetablihmentoftheSBoREtobenovel,unique andlikelytohavealatingimpact.Thiimpactwillnotonlybethroughthepub licationinScienceitelf,buthopefullythroughalargergroupofpublihin gplacethatmaywanttomodeltheirapproachafterScience."31.ItcanbelearnedfromParagraphIthat[A]Scienceintendtoimplifyitpeer-reviewproce.[B]journalaretrengtheningtheirtatiticalcheck.[C]fewjournalareblamedformitakeindataanalyi.32.Thephrae"flaggedup"(Para.2)ithecloetinmeaningto[A]found.[B]revied.[C]marked[D]tored33.GiovanniParmigianibelievethattheetablihmentoftheSBoREmay[A]poeathreattoallitpeer[B]meetwithtrongoppoition[C]increaeScience'circulation.[D]etane某ampleforotherjournal34.DavidVau某holdthatwhatScienceidoingnowA.addtoreearcher'worklod.B.diminihetheroleofreviewer.C.haroomforfurtherimprovement.D.itofailintheforeeeablefuture.35.Whichofthefollowingithebettitleofthete某tA.ScienceJoinPuhtoScreenStatiticinPaperB.ProfeionalStatiticianDeerveMoreRepectC.DataAnalyiFindItWayontoEditor'Dek31.Bjournalaretrengtheningtheirtatiticalcheck32.Bmarked33.Detane某ampleforotherjournal34.Charoomforfurtherimprovement35.AciencejoinPuhtocreentatiticinpaperTe某t3TheUS$3-millionFundamentalphyicprizeiindeedaninteretinge某periment,aAle某anderPolyakovaidwhenheacceptedthiyear’awardinMarch.Anditifarfro mtheonlyoneofittype.AaNewFeaturearticleinNaturedicue,atringofluc rativeawardforreearcherhavejoinedtheNobelPrizeinrecentyear.Many, liketheFundamentalPhyicPrize,arefundedfromthetelephone-number-izedbankaccountofInternetentrepreneur.Theebenefactorhaveucceededintheirchoenfield,theyay,andtheywanttouetheirwealthtodrawattenti ontothoewhohaveucceededincience.What’nottolikeQuitealot,accordingtoahandfulofcientitquotedi ntheNewFeature.Youcannotbuycla,atheoldayinggoe,andtheeuptartentr epreneurcannotbuytheirprizethepretigeoftheNobel,Thenewawardarean e某ercieinelf-promotionforthoebehindthem,aycientit.Theycouldditorttheachieveme nt-baedytemofpeer-review-ledreearch.Theycouldcementthetatuquoofpeer-reviewedreearch.Theydonotfundpeer-reviewedreearch.Theyperpetuatethemythofthelonegeniu.Thegoaloftheprize-givereemacatteredathecriticim.Somewanttohock,othertodrawpeoplein tocience,ortobetterrewardthoewhohavemadetheircareerinreearch.真题解析：文章主题及背景知识：此篇阅读的主题内容为“基础物理学奖”，如果对于这一背景信息有所了解，这篇文章便可轻松看懂，做题更是十拿九稳!与2022年相比，2022考研阅读文章同样注重时效性，Te某t3便是反应了2022年3月份的一次实时事件：基础物理学基金会于3月20日晚在瑞士日内瓦揭晓了2022年基础物理学奖!所以2022考研的同学们一定要多多关注社会热点话题，拓展视野，丰富自己的文化背景知识，这样才能取得事半功倍的效果!31.TheFundamentalPhyicalPrizeieena[A]aymboloftheentrepreneur’wealth.[B]apoiblereplacementoftheNobelPrize.[C]ane某ampleofbanker’invetment.[D]ahandomerewardforreearcher.答案：A为细节题。
Science has been a cornerstone of human progress,driving innovation,improving lives,and expanding our understanding of the universe.The benefits of science are manifold and farreaching,touching every aspect of our daily lives.Here are some of the key advantages that science offers:1.Health Advancements:One of the most significant contributions of science is in the field of medicine.Scientific research has led to the development of vaccines,antibiotics, and advanced surgical techniques,which have saved countless lives and improved the quality of life for many.2.Technological Innovation:The digital age we live in is a testament to the power of puters,smartphones,and the internet have revolutionized communication, education,and commerce,making the world more connected than ever before.3.Environmental Sustainability:Science plays a crucial role in understanding and addressing environmental issues such as climate change,pollution,and biodiversity loss. It provides the tools and knowledge necessary to develop sustainable practices and technologies.4.Economic Growth:Scientific discoveries and technological advancements are key drivers of economic growth.They create new industries,jobs,and opportunities for wealth generation,contributing to the overall prosperity of societies.cation and Knowledge:Science education is fundamental to developing a wellinformed and skilled workforce.It fosters critical thinking,problemsolving skills, and a deeper understanding of the world,which are essential for personal and societal development.6.Space Exploration:The exploration of space has been made possible through the application of scientific principles.It has not only expanded our knowledge of the cosmos but also led to the development of technologies that have practical applications on Earth.7.Agriculture and Food Security:Science has transformed agriculture,increasing crop yields and ensuring food security through genetically modified crops,improved irrigation systems,and sustainable farming practices.8.Disaster Prevention and Response:Scientific research helps in predicting natural disasters such as earthquakes,hurricanes,and tsunamis,allowing for better preparedness and response strategies to minimize loss of life and property.9.Social Progress:Science contributes to social progress by challenging and changing societal norms and beliefs.It promotes evidencebased decisionmaking and helps to debunk myths and superstitions.10.Cultural Understanding:The study of anthropology and archaeology,which are scientific disciplines,has enriched our understanding of human history and cultural diversity,fostering a greater appreciation for different cultures and traditions.In conclusion,the benefits of science are vast and varied,impacting every facet of human existence.It is a driving force for positive change and a key to unlocking the mysteries of our world.As we continue to push the boundaries of knowledge,the potential for science to improve our lives only grows.。
The Oxford 3000 wordlist▪a, an indefinite article ▪abandon v.▪abandoned adj.▪ability n.▪able adj.▪unable adj.▪about adv.,prep.▪above prep.,adv.▪abroad adv.▪absence n.▪absent adj.▪absolute adj.▪absolutely adv.▪absorb v.▪abuse n.,v.▪academic adj.▪accent n.▪accept v.▪acceptable adj.▪unacceptable adj.▪access n.▪accident n.▪by accident▪accidental adj.▪accidentally adv.▪accommodation n.▪accompany v.▪according to prep.▪account n.,v.▪accurate adj.▪accurately adv.▪accuse v.▪achieve v.▪achievement n.▪acid n.▪acknowledge v.▪acquire v.▪across adv.,prep.▪act n.,v.▪action n.▪take action▪active adj.▪actively adv.▪activity n.▪actor, actress n.▪actual adj.▪actually adv.▪ad advertisement▪adapt v.▪add v.▪addition n.▪in addition (to)▪additional adj.▪address n.,v.▪adequate adj.▪adequately adv.▪adjust v.▪admiration n.▪admire v.▪admit v.▪adopt v.▪adult n.,adj.▪advance n.,v.▪advanced adj.▪in advance▪advantage n.▪take advantage of▪adventure n.▪advertise v.▪advertising n.▪advertisement (also ad, advert) n.▪advice n.▪advise v.▪affair n.▪affect v.▪affection n.▪afford v.▪afraid adj.▪after prep.,conj.,adv.▪afternoon n.▪afterwards (especially BrE;NAmE usually afterward) adv.▪again adv.▪against prep.▪age n.▪aged adj.▪agency n.▪agent n.▪aggressive adj.▪ago adv.▪agree v.▪agreement n.▪ahead adv.▪aid n.,v.▪aim n.,v.▪air n.▪aircraft n.▪airport n.▪alarm n.,v.▪alarming adj.▪alarmed adj.▪alcohol n.▪alcoholic adj., n.▪alive adj.▪all det.,pron.,adv.▪allow v.▪all right adj.,adv.,exclamation▪ally n., v.▪allied adj.▪almost adv.▪alone adj.,adv.▪along prep.,adv.▪alongside prep.,adv.▪aloud adv.▪alphabet n.▪alphabetical adj.▪alphabetically adv.▪already adv.▪also adv.▪alter v.▪alternative n.,adj.▪alternatively adv.▪although conj.▪altogether adv.▪always adv.▪ a.m. (NAmE also A.M.) abbr.▪amaze v.▪amazing adj.▪amazed adj.▪ambition n.▪ambulance n.▪among (also amongst) prep.▪amount n., v.▪amuse v.▪amusing adj.▪amused adj.▪an a, an▪analyse (BrE) (NAmE analyze) v.▪analysis n.▪ancient adj.▪and conj.▪anger n.▪angle n.▪angry adj.▪angrily adv.▪animal n.▪ankle n.▪anniversary n.▪announce v.▪annoy v.▪annoying adj.▪annoyed adj.▪annual adj.▪annually adv.▪another det.,pron.▪answer n.,v.▪anti- prefix▪anticipate v.▪anxiety n.▪anxious adj.▪anxiously adv.▪any det.,pron.,adv.▪anyone (also anybody) pron.▪anything pron.▪anyway adv.▪anywhere adv.▪apart adv.▪apart from (also aside from especially in NAmE) prep.▪apartment n. (especially NAmE) ▪apologize (BrE also -ise) v.▪apparent adj.▪apparently adv.▪appeal n.,v.▪appear v.▪appearance n.▪apple n.▪application n.▪apply v.▪appoint v.▪appointment n.▪appreciate v.▪approach v.,n.▪appropriate adj.▪approval n.▪approve (of) v.▪approving adj.▪approximate adj.▪approximately adv.▪April n. (abbr. Apr.) ▪area n.▪argue v.▪argument n.▪arise v.▪arm n.,v.▪arms n.▪armed adj.▪army n.▪around adv.,prep.▪arrange v.▪arrangement n.▪arrest v.,n.▪arrival n.▪arrive v.▪arrow n.▪art n.▪article n.▪artificial adj.▪artificially adv.▪artist n.▪artistic adj.▪as prep.,adv.,conj.▪ashamed adj.▪aside adv.▪aside from apart from ▪ask v.▪asleep adj.▪fall asleep▪aspect n.▪assist v.▪assistance n.▪assistant n.,adj.▪associate v.▪associated with▪association n.▪assume v.▪assure v.▪at prep.▪atmosphere n.▪atom n.▪attach v.▪attached adj.▪attack n.,v.▪attempt n.,v.▪attempted adj.▪attend v.▪attention n.▪pay attention▪attitude n.▪attorney n. (especially NAmE) ▪attract v.▪attraction n.▪attractive adj.▪audience n.▪August n. (abbr. Aug.)▪aunt n.▪author n.▪authority n.▪automatic adj.▪automatically adv.▪autumn n. (especially BrE)▪available adj.▪average adj.,n.▪avoid v.▪awake adj.▪award n.,v.▪aware adj.▪away adv.▪awful adj.▪awfully adv.▪awkward adj.▪awkwardly adv.▪baby n.▪back n.,adj.,adv.,v.▪background n.▪backwards (also backward especially in NAmE) adv.▪backward adj.▪bacteria n.▪bad adj.▪go bad▪badly adv.▪bad-tempered adj.▪bag n.▪baggage n. (especially NAmE) ▪bake v.▪balance n.,v.▪ball n.▪ban v.,n.▪band n.▪bandage n., v.▪bank n.▪bar n.▪bargain n.▪barrier n.▪base n.,v.▪based on▪basic adj.▪basically adv.▪basis n.▪bath n.▪bathroom n.▪battery n.▪battle n.▪bay n.▪be v.,auxiliary v.▪beach n.▪beak n.▪bear v.▪beard n.▪beat n.,v.▪beautiful adj.▪beautifully adv.▪beauty n.▪because conj.▪because of prep.▪become v.▪bed n.▪bedroom n.▪beef n.▪beer n.▪before prep.,conj.,adv.▪begin v.▪beginning n.▪behalf n.: on behalf of sb, on sb’s behalf (BrE) (NAmE in behalf of sb, in sb’s behalf)▪behave v.▪behaviour (BrE) (NAmE behavior) n.▪behind prep.,adv.▪belief n.▪believe v.▪bell n.▪belong v.▪below prep.,adv.▪belt n.▪bend v.,n.▪bent adj.▪beneath prep.,adv.▪benefit n.,v.▪beside prep.▪bet v.,n.▪betting n.▪better, best good, well▪between prep.,adv.▪beyond prep.,adv.▪bicycle (also bike) n.▪bid v.,n.▪big adj.▪bill n.▪bin n. (BrE)▪biology n.▪bird n.▪birth n.▪give birth (to)▪birthday n.▪biscuit n. (BrE)▪bit n. (especially BrE)▪ a bit▪bite v.,n.▪bitter adj.▪bitterly adv.▪black adj.,n.▪blade n.▪blame v.,n.▪blank adj., n.▪blankly adv.▪blind adj.▪block n.,v.▪blonde adj., n., blond adj.▪blood n.▪blow v.,n.▪blue adj.,n.▪board n., v.▪on board▪boat n.▪body n.▪boil v.▪bomb n.,v.▪bone n.▪book n.,v.▪boot n.▪border n.▪bore v.▪boring adj.▪bored adj.▪born: be born v.▪borrow v.▪boss n.▪both det.,pron.▪bother v.▪bottle n.▪bottom n.,adj.▪bound adj.: bound to ▪bowl n.▪box n.▪boy n.▪boyfriend n.▪brain n.▪branch n.▪brand n.▪brave adj.▪bread n.▪break v.,n.▪broken adj.▪breakfast n.▪breast n.▪breath n.▪breathe v.▪breathing n.▪breed v.,n.▪brick n.▪bridge n.▪brief adj.▪briefly adv.▪bright adj.▪brightly adv.▪brilliant adj.▪bring v.▪broad adj.▪broadly adv.▪broadcast v.,n.▪broken break▪brother n.▪brown adj.,n.▪brush n.,v.▪bubble n.▪budget n.▪build v.▪building n.▪bullet n.▪bunch n.▪burn v.▪burnt adj.▪burst v.▪bury v.▪bus n.▪bush n.▪business n.▪businessman, businesswoman n.▪busy adj.▪but conj.▪butter n.▪button n.▪buy v.▪buyer n.▪by prep.,adv.▪bye exclamation▪ c abbr.cent▪cabinet n.▪cable n.▪cake n.▪calculate v.▪calculation n.▪call v.,n.▪be called▪calm adj.,v.,n.▪calmly adv.▪camera n.▪camp n.,v.▪camping n.▪campaign n.▪can modal v.,n.▪cannot▪could modal v.▪cancel v.▪cancer n.▪candidate n.▪candy n. (NAmE) ▪cap n.▪capable (of) adj.▪capacity n.▪capital n.,adj.▪captain n.▪capture v.,n.▪car n.▪card n.▪cardboard n.▪care n.,v.▪take care (of) ▪care for▪career n.▪careful adj.▪carefully adv.▪careless adj.▪carelessly adv.▪carpet n.▪carrot n.▪carry v.▪case n.▪in case (of)▪cash n.▪cast v.,n.▪castle n.▪cat n.▪catch v.▪category n.▪cause n.,v.▪CD n.▪cease v.▪ceiling n.▪celebrate v.▪celebration n.▪cell n.▪cellphone (also cellular phone) n. (especially NAmE)▪cent n. (abbr. c, ct)▪centimetre (BrE) (NAmEcentimeter) n. (abbr. cm)▪central adj.▪centre (BrE) (NAmE center) n.▪century n.▪ceremony n.▪certain adj.,pron.▪certainly adv.▪uncertain adj.▪certificate n.▪chain n., v.▪chair n.▪chairman, chairwoman n.▪challenge n.,v.▪chamber n.▪chance n.▪change v.,n.▪channel n.▪chapter n.▪character n.▪characteristic adj.,n.▪charge n.,v.▪in charge of▪charity n.▪chart n.,v.▪chase v.,n.▪chat v., n.▪cheap adj.▪cheaply adv.▪cheat v.,n.▪check v.,n.▪cheek n.▪cheerful adj.▪cheerfully adv.▪cheese n.▪chemical adj.,n.▪chemist n.▪chemist’s n. (BrE)▪chemistry n.▪cheque n. (BrE) (NAmE check) ▪chest n.▪chew v.▪chicken n.▪chief adj.,n.▪child n.▪chin n.▪chip n.▪chocolate n.▪choice n.▪choose v.▪chop v.▪church n.▪cigarette n.▪cinema n. (especially BrE) ▪circle n.▪circumstance n.▪citizen n.▪city n.▪civil adj.▪claim v.,n.▪clap v., n.▪class n.▪classic adj.,n.▪classroom n.▪clean adj.,v.▪clear adj.,v.▪clearly adv.▪clerk n.▪clever adj.▪click v., n.▪client n.▪climate n.▪climb v.▪climbing n.▪clock n.▪close /kl??s, NAmE klo?s/ adj.▪closely adv.▪close /kl??z, NAmE kl??z/ v.▪closed adj.▪closet n. (especially NAmE) ▪cloth n.▪clothes n.▪clothing n.▪cloud n.▪club n.▪cm abbr.centimetre▪coach n.▪coal n.▪coast n.▪coat n.▪code n.▪coffee n.▪coin n.▪cold adj.,n.▪coldly adv.▪collapse v.,n.▪colleague n.▪collect v.▪collection n.▪college n.▪colour (BrE) (NAmE color) n., v.▪coloured (BrE) (NAmE colored) adj.▪column n.▪combination n.▪combine v.▪come v.▪comedy n.▪comfort n.,v.▪comfortable adj.▪comfortably adv.▪uncomfortable adj.▪command v.,n.▪comment n.,v.▪commercial adj.▪commission n., v.▪commit v.▪commitment n.▪committee n.▪common adj.▪in common▪commonly adv.▪communicate v.▪communication n.▪community n.▪company n.▪compare v.▪comparison n.▪compete v.▪competition n.▪competitive adj.▪complain v.▪complaint n.▪complete adj.,v.▪completely adv.▪complex adj.▪complicate v.▪complicated adj.▪computer n.▪concentrate v.▪concentration n.▪concept n.▪concern v.,n.▪concerned adj.▪concerning prep.▪concert n.▪conclude v.▪conclusion n.▪concrete adj.,n.▪condition n.▪conduct v.,n.▪conference n.▪confidence n.▪confident adj.▪confidently adv.▪confine v.▪confined adj.▪confirm v.▪conflict n.,v.▪confront v.▪confuse v.▪confusing adj.▪confused adj.▪confusion n.▪congratulations n.▪congress n.▪connect v.▪connection n.▪conscious adj.▪unconscious adj.▪consequence n.▪conservative adj.▪consider v.▪considerable adj.▪considerably adv.▪consideration n.▪consist of v.▪constant adj.▪constantly adv.▪construct v.▪construction n.▪consult v.▪consumer n.▪contact n.,v.▪contain v.▪container n.▪contemporary adj.▪content n.▪contest n.▪context n.▪continent n.▪continue v.▪continuous adj.▪continuously adv.▪contract n.,v.▪contrast n.,v.▪contrasting adj.▪contribute v.▪contribution n.▪control n.,v.▪in control (of)▪under control▪controlled adj.▪uncontrolled adj.▪convenient adj.▪convention n.▪conventional adj.▪conversation n.▪convert v.▪convince v.▪cook v.,n.▪cooking n.▪cooker n. (BrE)▪cookie n. (especially NAmE) ▪cool adj.,v.▪cope (with) v.▪copy n.,v.▪core n.▪corner n.▪correct adj.,v.▪correctly adv.▪cost n.,v.▪cottage n.▪cotton n.▪cough v.,n.▪coughing n.▪could can▪council n.▪count v.▪counter n.▪country n.▪countryside n.▪county n.▪couple n.▪ a couple▪courage n.▪course n.▪of course▪court n.▪cousin n.▪cover v.,n.▪covered adj.▪covering n.▪cow n.▪crack n.,v.▪cracked adj.▪craft n.▪crash n.,v.▪crazy adj.▪cream n.,adj.▪create v.▪creature n.▪credit n.▪credit card n.▪crime n.▪criminal adj.,n.▪crisis n.▪crisp adj.▪criterion n.▪critical adj.▪criticism n.▪criticize (BrE also -ise) v.▪crop n.▪cross n.,v.▪crowd n.▪crowded adj.▪crown n.▪crucial adj.▪cruel adj.▪crush v.▪cry v.,n.▪ct abbr.cent▪cultural adj.▪culture n.▪cup n.▪cupboard n.▪curb v.▪cure v.,n.▪curious adj.▪curiously adv.▪curl v.,n.▪curly adj.▪current adj.,n.▪currently adv.▪curtain n.▪curve n.,v.▪curved adj.▪custom n.▪customer n.▪customs n.▪cut v.,n.▪cycle n.,v.▪cycling n.▪dad n.▪daily adj.▪damage n.,v.▪damp adj.▪dance n.,v.▪dancing n.▪dancer n.▪danger n.▪dangerous adj.▪dare v.▪dark adj.,n.▪data n.▪date n.,v.▪daughter n.▪day n.▪dead adj.▪deaf adj.▪deal v.,n.▪deal with▪dear adj.▪death n.▪debate n.,v.▪debt n.▪decade n.▪decay n.,v.▪December n. (abbr. Dec.)▪decide v.▪decision n.▪declare v.▪decline n.,v.▪decorate v.▪decoration n.▪decorative adj.▪decrease v.,n.▪deep adj.,adv.▪deeply adv.▪defeat v.,n.▪defence (BrE) (NAmE defense) n.▪defend v.▪define v.▪definite adj.▪definitely adv.▪definition n.▪degree n.▪delay n.,v.▪deliberate adj.▪deliberately adv.▪delicate adj.▪delight n.,v.▪delighted adj.▪deliver v.▪delivery n.▪demand n.,v.▪demonstrate v.▪dentist n.▪deny v.▪department n.▪departure n.▪depend (on) v.▪deposit n.,v.▪depress v.▪depressing adj.▪depressed adj.▪depth n.▪derive v.▪describe v.▪description n.▪desert n.,v.▪deserted adj.▪deserve v.▪design n.,v.▪desire n.,v.▪desk n.▪desperate adj.▪desperately adv.▪despite prep.▪destroy v.▪destruction n.▪detail n.▪in detail ▪detailed adj.▪determination n.▪determine v.▪determined adj.▪develop v.▪development n.▪device n.▪devote v.▪devoted adj.▪diagram n.▪diamond n.▪diary n.▪dictionary n.▪die v.▪dying adj.▪diet n.▪difference n.▪different adj.▪differently adv.▪difficult adj.▪difficulty n.▪dig v.▪dinner n.▪direct adj.,v.▪directly adv.▪direction n.▪director n.▪dirt n.▪dirty adj.▪disabled adj.▪disadvantage n.▪disagree v.▪disagreement n.▪disappear v.▪disappoint v.▪disappointing adj.▪disappointed adj.▪disappointment n.▪disapproval n.▪disapprove (of) v.▪disapproving adj.▪disaster n.▪disc (also disk, especially in NAmE) n.▪discipline n.▪discount n.▪discover v.▪discovery n.▪discuss v.▪discussion n.▪disease n.▪disgust v.,n.▪disgusting adj.▪disgusted adj.▪dish n.▪dishonest adj.▪dishonestly adv.▪disk n.▪dislike v.,n.▪dismiss v.▪display v.,n.▪dissolve v.▪distance n.▪distinguish v.▪distribute v.▪distribution n.▪district n.▪disturb v.▪disturbing adj.▪divide v.▪division n.▪divorce n.,v.▪divorced adj.▪do v.,auxiliary v.▪undo v.▪doctor n. (abbr. Dr, NAmE Dr.) ▪document n.▪dog n.▪dollar n.▪domestic adj.▪dominate v.▪door n.▪dot n.▪double adj.,det.,adv.,n.,v.▪doubt n.,v.▪down adv.,prep.▪downstairs adv.,adj., n.▪downwards (also downward especially in NAmE) adv.▪downward adj.▪dozen n.,det.▪Dr (BrE) (also Dr. NAmE, BrE) abbr.doctor▪draft n.,adj.,v.▪drag v.▪drama n.▪dramatic adj.▪dramatically adv.▪draw v.▪drawing n.▪drawer n.▪dream n.,v.▪dress n.,v.▪dressed adj.▪drink n.,v.▪drive v.,n.▪driving n.▪driver n.▪drop v.,n.▪drug n.▪drugstore n. (NAmE)▪drum n.▪drunk adj.▪dry adj.,v.▪due adj.▪due to▪dull adj.▪dump v.,n.▪during prep.▪dust n.,v.▪duty n.▪DVD n.▪each det.,pron.▪each other (also one another) pron.▪ear n.▪early adj.,adv.▪earn v.▪earth n.▪ease n.,v.▪east n.,adj.,adv.▪eastern adj.▪easy adj.▪easily adv.▪eat v.▪economic adj.▪economy n.▪edge n.▪edition n.▪editor n.▪educate v.▪educated adj.▪education n.▪effect n.▪effective adj.▪effectively adv.▪efficient adj.▪efficiently adv.▪effort n.▪ e.g. abbr.▪egg n.▪either det.,pron.,adv.▪elbow n.▪elderly adj.▪elect v.▪election n.▪electric adj.▪electrical adj.▪electricity n.▪electronic adj.▪elegant adj.▪element n.▪elevator n. (NAmE)▪else adv.▪elsewhere adv.▪email (also e-mail) n.,v.▪embarrass v.▪embarrassing adj.▪embarrassed adj.▪embarrassment n.▪emerge v.▪emergency n.▪emotion n.▪emotional adj.▪emotionally adv.▪emphasis n.▪emphasize (BrE also -ise) v.▪empire n.▪employ v.▪unemployed adj.▪employee n.▪employer n.▪employment n.▪unemployment n.▪empty adj.,v.▪enable v.▪encounter v.,n.▪encourage v.▪encouragement n.▪end n.,v.▪in the end▪ending n.▪enemy n.▪energy n.▪engage v.▪engaged adj.▪engine n.▪engineer n.▪engineering n.▪enjoy v.▪enjoyable adj.▪enjoyment n.▪enormous adj.▪enough det.,pron.,adv.▪enquiry (also inquiry especially in NAmE) n.▪ensure v.▪enter v.▪entertain v.▪entertaining adj.▪entertainer n.▪entertainment n.▪enthusiasm n.▪enthusiastic adj.▪entire adj.▪entirely adv.▪entitle v.▪entrance n.▪entry n.▪envelope n.▪environment n.▪environmental adj.▪equal adj.,n.,v.▪equally adv.▪equipment n.▪equivalent adj.,n.▪error n.▪escape v.,n.▪especially adv.▪essay n.▪essential adj.,n.▪essentially adv.▪establish v.▪estate n.▪estimate n.,v.▪etc. (full form et cetera)▪euro n.▪even adv.,adj.▪evening n.▪event n.▪eventually adv.▪ever adv.▪every det.▪everyone (also everybody) pron.▪everything pron.▪everywhere adv.▪evidence n.▪evil adj.,n.▪ex- prefix▪exact adj.▪exactly adv.▪exaggerate v.▪exaggerated adj.▪exam n.▪examination n.▪examine v.▪example n.▪excellent adj.▪except prep.,conj.▪exception n.▪exchange v.,n.▪in exchange (for)▪excite v.▪exciting adj.▪excited adj.▪excitement n.▪exclude v.▪excluding prep.▪excuse n.,v.▪executive n.,adj.▪exercise n.,v.▪exhibit v., n.▪exhibition n.▪exist v.▪existence n.▪exit n.▪expand v.▪expect v.▪expected adj.▪unexpected adj.▪unexpectedly adv.▪expectation n.▪expense n.▪expensive adj.▪experience n.,v.▪experienced adj.▪experiment n.,v.▪expert n.,adj.▪explain v.▪explanation n.▪explode v.▪explore v.▪explosion n.▪export v.,n.▪expose v.▪express v.,adj.▪expression n.▪extend v.▪extension n.▪extensive adj.▪extent n.▪extra adj.,n.,adv.▪extraordinary adj.▪extreme adj.,n.▪extremely adv.▪eye n.▪face n.,v.▪facility n.▪fact n.▪factor n.▪factory n.▪fail v.▪failure n.▪faint adj.▪faintly adv.▪fair adj.▪fairly adv.▪unfair adj.▪unfairly adv.▪faith n.▪faithful adj.▪faithfully adv.▪Yours faithfully (BrE) ▪fall v.,n.▪fall over▪false adj.▪fame n.▪familiar adj.▪family n.,adj.▪famous adj.▪fan n.▪fancy v.,adj.▪far adv.,adj.▪further adj.▪farm n.▪farming n.▪farmer n.▪farther, farthest far ▪fashion n.▪fashionable adj.▪fast adj.,adv.▪fasten v.▪fat adj.,n.▪father n.▪faucet n. (NAmE)▪fault n.▪favour (BrE) (NAmE favor) n.▪in favour/favor (of)▪favourite (BrE) (NAmE favorite) adj.,n.▪fear n.,v.▪feather n.▪feature n.,v.▪February n. (abbr. Feb.)▪federal adj.▪fee n.▪feed v.▪feel v.▪feeling n.▪fellow n.,adj.▪female adj.,n.▪fence n.▪festival n.▪fetch v.▪fever n.▪few det.,adj.,pron.▪ a few▪field n.▪fight v.,n.▪fighting n.▪figure n.,v.▪file n.▪fill v.▪film n.,v.▪final adj., n.▪finally adv.▪finance n.,v.▪financial adj.▪find v.▪find out sth ▪fine adj.▪finely adv.▪finger n.▪finish v.,n.▪finished adj.▪fire n.,v.▪set fire to▪firm n.,adj.,adv.▪firmly adv.▪first det.,ordinal number,adv., n.▪at first▪fish n.,v.▪fishing n.▪fit v.,adj.▪fix v.▪fixed adj.▪flag n.▪flame n.▪flash v.,n.▪flat adj.,n.▪flavour (BrE) (NAmE flavor) n., v.▪flesh n.▪flight n.▪float v.▪flood n.,v.▪floor n.▪flour n.▪flow n.,v.▪flower n.▪flu n.▪fly v.,n.▪flying adj.,n.▪focus v.,n.▪fold v.,n.▪folding adj.▪follow v.▪following adj.,n.,prep.▪food n.▪foot n.▪football n.▪for prep.▪force n.,v.▪forecast n., v.▪foreign adj.▪forest n.▪forever (BrE also for ever) adv.▪forget v.▪forgive v.▪fork n.▪form n.,v.▪formal adj.▪formally adv.▪former adj.▪formerly adv.▪formula n.▪fortune n.▪forward (also forwards) adv.▪forward adj.▪found v.▪foundation n.▪frame n.,v.▪free adj.,v.,adv.▪freely adv.▪freedom n.▪freeze v.▪frozen adj.▪frequent adj.▪frequently adv.▪fresh adj.▪freshly adv.▪Friday n. (abbr. Fri.)▪fridge n. (BrE)▪friend n.▪make friends (with) ▪friendly adj.▪unfriendly adj.▪friendship n.▪frighten v.▪frightening adj.▪frightened adj.▪from prep.▪front n.,adj.▪in front (of)▪frozen freeze▪fruit n.▪fry v., n.▪fuel n.▪full adj.▪fully adv.▪fun n.,adj.▪make fun of▪function n.,v.▪fund n.,v.▪fundamental adj.▪funeral n.▪funny adj.▪fur n.▪furniture n.▪further, furthest far▪future n.,adj.▪g abbr.gram▪gain v.,n.▪gallon n.▪gamble v.,n.▪gambling n.▪game n.▪gap n.▪garage n.▪garbage n. (especially NAmE) ▪garden n.▪gas n.▪gasoline n. (NAmE)▪gate n.▪gather v.▪gear n.▪general adj.▪generally adv.▪in general▪generate v.▪generation n.▪generous adj.▪generously adv.▪gentle adj.▪gently adv.▪gentleman n.▪genuine adj.▪genuinely adv.▪geography n.▪get v.▪get on▪get off▪giant n.,adj.▪gift n.▪girl n.▪girlfriend n.▪give v.▪give sth away ▪give sth out ▪give (sth) up ▪glad adj.▪glass n.▪glasses n.▪global adj.▪glove n.▪glue n.,v.▪gm abbr.gram ▪go v.▪go down▪go up▪be going to ▪goal n.▪god n.▪gold n.,adj.▪good adj.,n.▪good at▪good for▪goodbye exclamation,n.▪goods n.▪govern v.▪government n.▪governor n.▪grab v.▪grade n., v.▪gradual adj.▪gradually adv.▪grain n.▪gram (BrE also gramme) n.(abbr.g, gm)▪grammar n.▪grand adj.▪grandchild n.▪granddaughter n.▪grandfather n.▪grandmother n.▪grandparent n.▪grandson n.▪grant v.,n.▪grass n.▪grateful adj.▪grave n.,adj.▪gray (NAmE ) grey▪great adj.▪greatly adv.▪green adj.,n.▪grey (BrE) (NAmE usually gray) adj.,n.▪grocery (NAmE usually grocery store) n.▪groceries n.▪ground n.▪group n.▪grow v.▪grow up▪growth n.▪guarantee n.,v.▪guard n.,v.▪guess v.,n.▪guest n.▪guide n.,v.▪guilty adj.▪gun n.▪guy n.▪habit n.▪hair n.▪hairdresser n.▪half n.,det.,pron.,adv.▪hall n.▪hammer n.▪hand n.,v.▪handle v.,n.▪hang v.▪happen v.▪happiness n.▪unhappiness n.▪happy adj.▪happily adv.▪unhappy adj.▪hard adj.,adv.▪hardly adv.▪harm n.,v.▪harmful adj.▪harmless adj.▪hat n.▪hate v., n.▪hatred n.▪have v., auxiliary v.▪have to modal v.▪he pron.▪head n.,v.▪headache n.▪heal v.▪health n.▪healthy adj.▪hear v.▪hearing n.▪heart n.▪heat n.,v.▪heating n.▪heaven n.▪heavy adj.▪heavily adv.▪heel n.▪height n.▪hell n.▪hello exclamation,n.▪help v.,n.▪helpful adj.▪hence adv.▪her pron.,det.▪hers pron.▪here adv.▪hero n.▪herself pron.▪hesitate v.▪hi exclamation▪hide v.▪high adj.,adv.▪highly adv.▪highlight v.,n.▪highway n. (especially NAmE) ▪hill n.▪him pron.▪himself pron.▪hip n.▪hire v.,n.▪his det.,pron.▪historical adj.▪history n.▪hit v.,n.▪hobby n.▪hold v.,n.▪hole n.▪holiday n.▪hollow adj.▪holy adj.▪home n.,adv..▪homework n.▪honest adj.▪honestly adv.▪honour (BrE) (NAmE honor) n.▪in honour/honor of▪hook n.▪hope v.,n.▪horizontal adj.▪horn n.▪horror n.▪horse n.▪hospital n.▪host n.,v.▪hot adj.▪hotel n.▪hour n.▪house n.▪housing n.▪household n.,adj.▪how adv.▪however adv.▪huge adj.▪human adj.,n.▪humorous adj.▪humour (BrE) (NAmE humor) n.▪hungry adj.▪hunt v.▪hunting n.▪hurry v.,n.▪in a hurry▪hurt v.▪husband n.▪I pron.▪ice n.▪ice cream n.▪idea n.▪ideal adj.,n.▪ideally adv.▪identify v.▪identity n.▪i.e. abbr.▪if conj.▪ignore v.▪ill adj. (especially BrE) ▪illegal adj.▪illegally adv.▪illness n.▪illustrate v.▪image n.▪imaginary adj.▪imagination n.▪imagine v.▪immediate adj.▪immediately adv.▪immoral adj.▪impact n.▪impatient adj.▪impatiently adv.▪implication n.▪imply v.▪import n.,v.▪importance n.▪important adj.▪importantly adv.▪unimportant adj.▪impose v.▪impossible adj.▪impress v.▪impressed adj.▪impression n.▪impressive adj.▪improve v.▪improvement n.▪in prep.,adv.▪inability n.▪inch n.▪incident n.▪include v.▪including prep.▪income n.▪increase v.,n.▪increasingly adv.▪indeed adv.▪independence n.▪independent adj.▪independently adv.▪index n.▪indicate v.▪indication n.▪indirect adj.▪indirectly adv.▪individual adj.,n.▪indoors adv.▪indoor adj.▪industrial adj.▪industry n.▪inevitable adj.▪inevitably adv.▪infect v.▪infected adj.▪infection n.▪infectious adj.▪influence n.,v.▪inform v.▪informal adj.▪information n.▪ingredient n.▪initial adj.,n.▪initially adv.▪initiative n.▪injure v.▪injured adj.▪injury n.▪ink n.▪inner adj.▪innocent adj.▪inquiry enquiry▪insect n.▪insert v.▪inside prep.,adv.,n.,adj.▪insist (on) v.▪install v.▪instance n.▪for instance▪instead adv.▪instead of▪institute n.▪institution n.▪instruction n.▪instrument n.▪insult v.,n.▪insulting adj.▪insurance n.▪intelligence n.▪intelligent adj.▪intend v.▪intended adj.▪intention n.▪interest n.,v.▪interesting adj.▪interested adj.▪interior n.,adj.▪internal adj.▪international adj.▪Internet n.▪interpret v.▪interpretation n.▪interrupt v.▪interruption n.▪interval n.▪interview n.,v.▪into prep.▪introduce v.▪introduction n.▪invent v.▪invention n.▪invest v.▪investigate v.▪investigation n.▪investment n.▪invitation n.▪invite v.▪involve v.▪involved in▪involvement n.▪iron n.,v.▪irritate v.▪irritating adj.▪irritated adj.▪-ish suffix▪island n.▪issue n.,v.▪it pron.,det.▪its det.▪item n.▪itself pron.▪jacket n.▪jam n.▪January n. (abbr. Jan.)▪jealous adj.▪jeans n.▪jelly n.▪jewellery (BrE) (NAmE jewelry) n.▪job n.▪join v.▪joint adj.,n.▪jointly adv.▪joke n.,v.▪journalist n.▪journey n.▪joy n.▪judge n.,v.▪judgement (also judgment especially in NAmE) n.▪juice n.▪July n. (abbr. Jul.)▪jump v.,n.▪June n. (abbr. Jun.)▪junior adj.,n.▪just adv.▪justice n.▪justify v.▪justified adj.▪k abbr.kilometre▪keen adj.▪keen on▪keep v.▪key n.,adj.▪keyboard n.▪kick v.,n.▪kid n.▪kill v.▪killing n.▪kilogram (BrE also kilogramme) (also kilo) n. (abbr. kg)。
The Debate: Prioritizing Fundamentals or CreativityIn the realm of learning and development, there has always been a debate between prioritizing fundamentals and fostering creativity. While both play crucial roles in personal and professional growth, the question remains: which should be the focus?The Importance of FundamentalsFundamentals are the building blocks of any skill or knowledge. They provide a solid foundation upon which more complex ideas and concepts can be built. In the world of academics, for example, mastering the basics of math or science is essential for understanding more advanced theories. Similarly, in the workplace, having a strong grasp of basic skills like communication or time management is crucial for success.By prioritizing fundamentals, individuals ensure that they have a solid understanding of the core principles and can apply them in various situations. This approach fosters consistency and reliability, which are highly valued in both academic and professional settings.The Value of CreativityHowever, while fundamentals are essential, creativity is what propels us forward. It is the engine of innovation and the driving force behind progress. In today's rapidly changing world, the ability to think outside the box and generate new ideas is invaluable.Creativity encourages individuals to explore uncharted territories, challenge conventional wisdom, and push the boundaries of what's possible. It fosters a mindset of experimentation and risk-taking, which can lead to groundbreaking discoveries and transformative solutions.Finding the BalanceThe truth is, there is no one-size-fits-all answer to the question of prioritizing fundamentals or creativity. It depends on the context, the individual's goals, and the demands of the environment.In academic settings, for example, students need to master the basics to build a solid foundation of knowledge. However, they should also be encouraged to think creatively and explore new ideas. Similarly, in the workplace, employees need to have a strong grasp of basic skills, but they should also be given the freedom to innovate and experiment.The key is to find the right balance between the two. This requires a nuanced understanding of when to focus on fundamentals and when to encourage creativity. It also requires a culture that values both approaches and provides opportunities for individuals to develop both their fundamental skills and their creative abilities.ConclusionUltimately, the debate between prioritizing fundamentals and creativity is not an either-or proposition. Both are crucial for personal and professional growth. The challenge lies in finding the right balance between the two, depending on the context and the goals at hand. By doing so, we can ensure that we have a solid foundation of knowledge and skills while also maintaining the flexibility and creativity necessary to navigate the complexities of the modern world.。
fundamentalIntroductionFundamental is a word root that comes from the Latin word “fundamentum,” which means “foundation.” It is used to denote something essential, basic, or foundational. In various fields and disciplines, the term fundamental plays a crucial role. Whether it is in science, mathematics, music, or philosophy, understanding the fundamental principles and concepts is vital for building a strong knowledge base.The Fundamentals in ScienceThe Scientific Method: The Fundamental Approach1.Observation: The scientific method begins with observation, wherescientists carefully observe and gather data about a specificphenomenon.2.Question: Based on the observations, scientists develop questionsthat they want to investigate further.3.Hypothesis: A hypothesis is a proposed explanation for theobserved phenomenon. It is a fundamental step in the scientificmethod as it forms the basis for further experimentation.4.Experimentation: Scientists design and conduct experiments totest their hypothesis. These experiments follow specific protocolsand guidelines to ensure accuracy and validity.5.Analysis: After conducting experiments, scientists analyze thedata collected to draw conclusions and determine whether theirhypothesis is supported or refuted.6.Conclusion: The final step involves drawing conclusions based onthe results obtained from the experiments. These conclusions formthe basis for further scientific research and the development oftheories and laws.Fundamental Laws and Principles1.Newton’s Three Laws of Motion:Sir Isaac Newton’s laws ofmotion are considered fundamental laws in classical physics. They describe the relationship between the motion of an object and the forces acting upon it.•Newton’s First Law: An object at rest will stay at rest, and an object in motion will continue moving at a constant velocityunless acted upon by an external force.•Newton’s Second Law: The acceleration of an object is directly proportional to the net force acting upon it and inverselyproportional to its mass.•Newton’s Third Law: For every action, there is an equal and opposite reaction.w of Conservation of Energy: Energy cannot be created ordestroyed; it can only be transferred or transformed from one form to another. This fundamental principle is the basis of manyscientific studies, including thermodynamics and electricity.3.Cell Theory: The cell theory is a fundamental concept in biology.It states that all living organisms are composed of cells, andcells are the basic structural and functional units of life.4.Theory of Evolution:Charles Darwin’s theory of evolution is afundamental principle in biology that explains how species haveevolved over time through natural selection and genetic variation. The Fundamentals in MathematicsFundamental Mathematical Concepts1.Numbers and Operations: Numbers are the fundamental buildingblocks of mathematics. Understanding the properties and operations of different types of numbers (e.g., integers, fractions, andirrational numbers) is essential for mathematical proficiency.2.Algebraic Expressions and Equations: Algebra is a fundamentalbranch of mathematics that deals with the manipulation of symbols and solving equations. It provides a foundation for higher-levelmathematical concepts and problem-solving skills.3.Geometry: Geometry is concerned with the study of shapes, sizes,and spatial relationships. It is a fundamental branch ofmathematics that has practical applications in various fields,such as architecture, engineering, and graphics.4.Calculus: Calculus is a fundamental branch of mathematics thatdeals with rates of change and the accumulation of quantities. It is widely used in physics, engineering, economics, and many other scientific disciplines.5.Probability and Statistics: Probability and statistics arefundamental concepts for understanding uncertainty and makinginformed decisions based on data. They play a crucial role infields such as finance, medicine, and social sciences.Fundamental Theorems and Formulas1.Pythagorean Theorem: The Pythagorean theorem states that in aright-angled triangle, the square of the hypotenuse is equal tothe sum of the squares of the other two sides.2.Fundamental Theorem of Calculus: The fundamental theorem ofcalculus establishes the relationship between differentiation and integration. It states that if a function is continuous on aclosed interval, then the area under its curve can be determinedby evaluating the antiderivative of the function at the endpoints of the interval.3.Fundamental Theorem of Algebra: The fundamental theorem ofalgebra states that every non-constant polynomial equation withcomplex coefficients has at least one complex root.The Fundamentals in MusicMusical Fundamentals1.Pitch and Melody: Pitch is the fundamental characteristic ofsound that determines its highness or lowness. Melody is thearrangement of pitches in a particular sequence, forming a musical line or tune.2.Rhythm and Beat: Rhythm is the pattern of sounds and silences inmusic, while beat is the steady pulse that divides the music into regular units of time.3.Harmony: Harmony refers to the combination of different pitchesplayed simultaneously, creating chords and chord progressions. It adds depth and richness to music.4.Dynamics and Expressiveness: Dynamics refers to the variations inloudness and softness in music, while expressiveness relates tothe interpretation and emotional qualities conveyed throughmusical performance.5.Musical Notation: Musical notation is a system of writing downmusic using symbols and musical symbols, making it possible tonotate and transmit musical ideas over time.Fundamental Musical Practices1.Scales and Modes: Scales and modes are fundamental frameworks fororganizing pitches in music. They provide a structure for melodies and harmonies.2.Chords and Chord Progressions: Chords are formed by combiningthree or more pitches played simultaneously. Chord progressionsprovide a sequence of chords that creates harmonic movement andsupports the melody.3.Form: Musical form refers to the organization and structure of apiece of music. Common forms include binary form, ternary form,and sonata form.4.Improvisation: Improvisation is the spontaneous creation of musicin real-time, often associated with jazz and other improvisational genres.5.Performance and Interpretation: Performance and interpretationinvolve bringing music to life through expressive and skillfulexecution. It requires a deep understanding of the fundamentalaspects of music and artistic expression.ConclusionThe term fundamental is pervasive in various fields and disciplines, from science and mathematics to music and beyond. Understanding the fundamental principles, laws, and concepts forms the building blocks for deeper knowledge and exploration. By grasping the fundamentals, individuals can build a strong foundation to expand their understanding and make meaningful contributions within their chosen fields.。
Advances in Education 教育进展, 2023, 13(3), 1315-1320 Published Online March 2023 in Hans. https:///journal/ae https:///10.12677/ae.2023.133207全过程人民民主融入中学思想政治课教学探究 陈小念*，杨 又绍兴文理学院马克思主义学院，浙江 绍兴收稿日期：2023年2月20日；录用日期：2023年3月21日；发布日期：2023年3月28日摘要 全过程人民民主是中国民主政治的重大理论创新与实践成果，将其融入思想政治课教学是贯彻党的教育方针的必然旨趣，有利于落实立德树人的根本任务、提升学生民主参与意识。
将全过程人民民主融入思想政治课还存在一定的问题与困境，即全过程人民民主教学体系有待系统化，其体系和内容博大、教师与学生掌握和理解存在一定难度，其作为一种政治实践行为与学校理论教学存在一定脱节。
基于此，学校在未来教学中应重点更新教学理念，提升教师民主素养，创新教材体系，丰富教学内容，充分利用数字平台，优化教学手段。
关键词二十大，全过程人民民主，中学思想政治课教学Exploration of Integrating Whole Process of People’s Democracy into the Middle School Ideological and Political TeachingXiaonian Chen *, You YangSchool of Marxism, Shaoxing University, Shaoxing Zhejiang Received: Feb. 20th , 2023; accepted: Mar. 21st , 2023; published: Mar. 28th , 2023AbstractThe whole process of people’s democracy is the great theoretical innovation and practical results of China’s democratic politics. Integrating it into the ideological and political teaching is the in-evitable purview of implementing the Party’s educational policy, which is conducive to the imple-*通讯作者。
科学的几种形式英语作文Title: Various Forms of Science: Exploring the Depths。
Science is a multifaceted discipline, encompassing various forms and approaches that contribute to our understanding of the world around us. From empirical research to theoretical frameworks, science manifests in diverse ways, each offering unique insights and methodologies. In this essay, we will delve into several forms of science, exploring their characteristics, significance, and contributions to human knowledge.1. Empirical Science: Empirical science relies on observation and experimentation to validate hypotheses and theories. It emphasizes the importance of evidence obtained through sensory experience. This form of science is characterized by systematic data collection, rigorous experimentation, and the application of the scientific method. Through empirical science, researchers gather empirical evidence to support or refute scientific claims,leading to the development of new theories and the advancement of knowledge across various fields.2. Theoretical Science: Theoretical science involves the formulation of abstract models, concepts, and frameworks to explain natural phenomena. Unlike empirical science, which focuses on observation and experimentation, theoretical science relies on mathematical and conceptual reasoning to develop hypotheses and predict outcomes. Theoretical physicists, for example, use mathematical equations and theoretical frameworks to describe the fundamental forces of nature and the behavior of particles at the subatomic level. Theoretical science plays a crucial role in shaping our understanding of the universe and guiding empirical research.3. Applied Science: Applied science seeks to solve practical problems and address real-world challenges by applying scientific knowledge and principles. It involves the practical application of scientific theories and methodologies to develop technologies, products, and solutions that benefit society. Examples of applied scienceinclude engineering, medicine, agriculture, and environmental science. Applied science bridges the gap between theoretical knowledge and practical applications, driving innovation and technological advancement in various fields.4. Interdisciplinary Science: Interdisciplinary science integrates knowledge and methodologies from multiple disciplines to address complex issues and phenomena. It involves collaboration across disciplinary boundaries, drawing insights from diverse fields to gain a comprehensive understanding of complex systems and phenomena. Interdisciplinary approaches are increasingly important in tackling contemporary challenges such as climate change, public health, and sustainable development. By combining perspectives from different disciplines, interdisciplinary science fosters innovation and promotes holistic solutions to complex problems.5. Social Science: Social science investigates human behavior, society, and culture using empirical and theoretical methods. It encompasses disciplines such aspsychology, sociology, anthropology, economics, andpolitical science. Social scientists study various aspectsof human society, including social interactions, institutions, norms, and inequalities. Social science research informs public policy, contributes to our understanding of human behavior, and addresses socialissues such as poverty, inequality, and discrimination.6. Natural Science: Natural science is concerned with the study of the natural world and the physical universe.It includes disciplines such as physics, chemistry, biology, astronomy, and geology. Natural scientists seek to understand the fundamental laws and principles governingthe natural world, from the behavior of subatomic particles to the structure of galaxies. Natural science encompasses both empirical and theoretical approaches, ranging from laboratory experiments to astronomical observations. It provides insights into the origins, evolution, and dynamics of the cosmos and the Earth.In conclusion, science manifests in various forms, each with its own methodologies, approaches, and areas of focus.From empirical research and theoretical modeling to applied technologies and interdisciplinary collaborations, science plays a vital role in expanding human knowledge, solving practical problems, and addressing complex challenges. By embracing diverse forms of science and fostering interdisciplinary collaboration, we can continue to explore the depths of the unknown and unlock new discoveries that enrich our understanding of the world.。
摘要汽轮机旁路系统是现代单元机组热力系统的一个组成部分。
它的功能是，当锅炉和汽轮机的运行情况不相匹配时，即锅炉产生的蒸汽量大于汽轮机所需要的蒸汽量时，多余部分可以不进入汽轮机而经过旁路减温减压后直接引入凝汽器。
此外，有的旁路还承担着将锅炉的主蒸汽经减温减压后直接引入再热器的任务，以保护再热器的安全。
旁路系统的这些功能在机组启动、降负荷或甩负荷时是十分需要的。
当机组冷态启动时，在汽轮机冲转、升速或开始带负荷时锅炉产生的蒸汽量要比汽轮机需要的蒸汽量大，此时旁路系统可作为启动排汽用。
这样，锅炉可以独立地建立与汽轮机相适应的汽温和汽压，保证二者良好的综合启动，从而缩短了机组的启动时间，也延长了汽轮机的使用寿命。
与向空排气相比及回收了工质，又消除了噪音污染。
在机组迅速降负荷时，要求汽轮机迅速关小主汽门，而同时锅炉只可能缓慢的降负荷，即锅炉跟不上要求，此时旁路系统起着减压阀的作用。
这种情况下，旁路系统的存在使锅炉能独立与汽轮机而继续运行。
降负荷幅度越大，越迅速，越显示其优越性。
对于甩负荷事故情况，旁路系统能使锅炉保持在允许的蒸发量下运行，把多余的蒸汽引往凝汽器。
让运行人员有时间去判断甩负荷的原因，并决定锅炉负荷是应进一步下降还是继续保持下去，以便汽轮发电机组很快重新并网。
关键词大型火电机组，旁路控制，运行调试AbstractLarge-unit is the main power of electricity industry, along with global energy Insufficiency and progress ofenvironment consciousness, now surpercritical and ultra-supercitical units that are high efficiency and low emission have been outstanding epquipmengts in the world. large –unit reprsents the tadvanced thermal process theoty, material science and automatic technology. cooperating control between bypass system and large-unit. with safety, high efficiency, low emission, which have close relationship with economic benefit[17].Bypass system is important auxiliary equipment of operation of large-unit, and has many funcions, such as coopreating startup, recycling process fluid, reducing consumption, decreasing emission. Bypass system has several process steps, including pressure reduction, desuperheating etc, and adopts automatic control method under different operation modes.Typical big unti bypass system comprises of high pressure bypass and low pressure bypass, individually executes different functions in unti operation. Bypass system operation control shall correspond with unit control system operation, and equip interlock device.Adding-bypass system is a system project, through bypass design, operation control mode selection, key element choice, system match, installation and commission, excellent cooperati ve startup among untis, to complete relevant functions.Bypass system has achieved widely domestic appliance, and achieves some effect on safety opreation, combined load cooperation and economic benefit, while unveiling some problems to be resolved[19].Further research of large-unit bypass system thermal process theory, thermal process matri al, fundamental element and automatic control, and accumulating exprerience during practice, co ntunuously improving design level and matching quality, are necessary route for gradually perfecting bypass system functions, improving operation safety and reliability, achieving highereconomic benefit.Key Words Large Power Unit, Bypass Control, Cooperative Regulation目录摘要IAbstractII目录III1引言11.1旁路控制系统的简介11.2旁路控制系统的功能22旁路控制系统42.1旁路控制系统的组成42.1.1旁路调节阀42.1.2液压动力单元和液压执行机构52.2旁路控制系统的工作方式52.2.1启动方式52.2.2运行方式52.3旁路控制系统的控制方式73分散控制系统83.1分散控制系统简述83.2 Symphony控制系统设计中采用的各种模件及其介绍83.3针对硬件的说明93.4设计中用到的部分功能码104汽轮机组旁路控制系统设计124.1设计思想124.2高压旁路控制系统124.2.1高压旁路控制系统的主要作用124.2.2高压旁路控制系统的工作原理12 4.2低压旁路控制系统165汽轮机组旁路控制系统分析185.1高压旁路压力控制分析185.1.1自动控制分析185.1.2手动控制分析195.2高压旁路温度控制分析205.2.1自动控制分析205.2.2手动控制分析215.3低压旁路温度控制分析215.3.1自动控制分析215.3.2手动控制分析225.4低压旁路压力控制分析225.4.1自动控制分析225.4.2手动控制分析236结论24致谢25参考文献261引言1.1旁路控制系统的简介汽轮机旁路控制系统（BPC）是指与汽轮机并联的蒸汽减温减压系统。
想要了解的事物英语作文There are so many things in this world that I want to understand better. From the smallest particles that make up the universe to the grandest mysteries of the cosmos, the sheer vastness of human knowledge and the unknown is both humbling and exhilarating. Every day, new discoveries are being made that expand the boundaries of what we know, and I find myself constantly in awe of the incredible complexity and beauty of our reality.One of the areas I'm most fascinated by is the field of quantum physics. The counterintuitive behaviors of subatomic particles, like the fact that they can exist in multiple states simultaneously, have always captivated me. I would love to gain a deeper understanding of concepts like quantum entanglement, wave-particle duality, and the uncertainty principle. How can particles that are separated by vast distances instantly influence each other? What is the true nature of reality at the most fundamental level? These are the kinds of questions that keep me up at night, pondering the very fabric of existence.At the same time, I'm also deeply interested in the workings of the human mind and consciousness. How do our brains process information and give rise to the rich inner experience of thoughts, emotions, and sensations? What is the relationship between the physical brain and the subjective self? The field of neuroscience has made incredible strides in mapping the neural pathways and mechanisms underlying various cognitive functions, but there is still so much we don't understand about the emergent phenomenon of consciousness.I'm also endlessly curious about the origins and evolution of life on our planet. How did the first self-replicating molecules arise from the primordial soup, and what were the key evolutionary steps that led to the incredible diversity of life we see today? What are the fundamental principles and mechanisms that drive the evolution of species, and how do they interact with the ever-changing environment? The more I learn about biology and the history of life, the more I realize how little we truly know about the origins and mechanics of the living world.Another area that fascinates me is the vastness of the cosmos and our place within it. The scale of the universe, with its billions of galaxies separated by unimaginable distances, is almost incomprehensible to the human mind. What is the true nature of space and time? How did the universe begin, and what is its ultimatefate? Will we ever unravel the mysteries of dark matter and dark energy, the enigmatic components that seem to make up the majority of the universe? The more we learn, the more questions arise, and I'm driven to understand our place in this grand cosmic tapestry.Of course, there are also countless aspects of the human experience that I wish I could understand better. What are the roots of human behavior, and how do our evolutionary and cultural histories shape the way we think and act? How do we form meaningful connections with others, and what are the psychological and neurological underpinnings of love, empathy, and social bonds? What is the nature of consciousness, and how do subjective experiences emerge from the physical brain? These are the kinds of deep, existential questions that captivate me and drive my curiosity.Ultimately, I believe that the pursuit of knowledge and understanding is one of the most noble and rewarding endeavors a human being can undertake. The more we learn about the world and the universe around us, the more we realize how much we still have to discover. And with each new insight, we gain a deeper appreciation for the incredible complexity and beauty of our reality. It is a never-ending journey of exploration and discovery, and I am honored to be a part of it. There is simply so much I want tounderstand, and I can't wait to continue on this wondrous path of learning and growth.。
Fundamentals of Management (2) Economics 4 Wang Shuo 41079075 Q1: Under what circumstances are short-term plans preferred? Under what circumstances are specific plans preferred?A1:Firstly, I’d like to talk about the differences betweenshort-term plans and long-term plans. Obviously, short-term plans are those that cover less than one year, and any plan covers more than five years is classified as long- term plans.Asto choosing short-term plans or long-term plans , this is what I think. For example, the more an organization’s current plans affect future commitments,the longer the time frame that management should use, that is if an organization considers its long-term development, it will use long-term plans.And in a long time , it won’t change. On the contrary ,the greater the uncertainty,the more plans should be of the short-term variety.That is , if rapid or important and technological, ecomomic,legal, or other changes are taking place, well-defined and precisely charactered routes are more likely to hinder an organization’s performance than to aid it. Short-term plans allow for more flexibility.Q2:What is SWOT analysis?A2: The SWOT is an analysis of Strengths , Weaknesses ,Opportunities and Threats in order to identify a strategic niche that the organization can exploit. Based on the SWOT analysis and identification of the organization’s opportunities , management reevaluates whether its mission and objectives are realistic, whether they need modification,and where any needed changes are likely to originate.On the other hand,if no change are necessary ,management is ready to begin the actual formulation of strategies.Q3:Organizations that fail to plan are planning to fail.Do you agree or disagree with this statement? Explain your position. A3:Firstly, I’d like to say I don’t agree with this statement partially. Before I explain my opinion, I want to talk about the plans.Plans involve short-term plans and long-term plans. We know that short-term plans are changeable, so even you have planned something totally, it may change. When changes happen, it doesn’t mean that you are going to fail or you are planning to fail .You can change these short-term plans instantly. And the organization can work as expected .As for long-term plans, in some degree , they can’t be changed .These plans will direct the organization to the right way. And they will affect your organization’s future development. If managers fail to plan ,he or she can’t change his or her long-term plans instantly.It will have a great impact on its future development.At this rate , if an organization fail to plan are planning to fail.。
自然语言处理及计算语言学相关术语中英对译表二自然语言处理及计算语言学相关术语中英对译表二 delimiter 定界符号 [定界符]denotation 外延denotic logic 符号逻辑dependency 依存关系dependency gram r 依存关系语法dependency relation 依存关系depth-first search 深度优先搜寻derivation 派生derivational bound morpheme 派生性附着语素descriptive gram r 描述型语法 [描写语法]descriptive linguistics 描述语言学 [描写语言学] desiderative 意愿的determiner 限定词deterministic algorithm 决定型算法 [确定性算法] deterministic finite state auto ton 决定型有限状态机deterministic parser 决定型语法剖析器 [确定性句法剖析程序] developmental psychology 开展心理学diachronic linguistics 历时语言学diacritic 附加符号dialectology 方言学dictionary database 辞典数据库 [词点数据库]dictionary entry 辞典条目digital pro ssing 数字处理 [数值处理] diglossia 双言digraph 二合字母diminutive 指小词diphone 双连音directed acyclic graph 有向非循环图disambiguation 消除歧义 [歧义消除] discourse 篇章discourse ysis 篇章分析 [言谈分析] discourse planning 篇章规划discourse representation theory 篇章表征理论 [言谈表示理论] discourse strategy 言谈策略discourse structure 言谈结构discrete 离散的disjunction 选言dissimilation 异化distributed 分布式的distributed cooperative reasoning 分布协调型推理distributed text parsing 分布式文本剖析disyllabic 双音节的ditransitive verb 双宾动词 [双宾语动词;双及物动词]divergen 扩散[分化]d-m (determiner-measure) construction 定量结构d-n (determiner-noun) construction 定名结构document retrieval system 文件检索系统 [文献检索系统] do in dependency 领域依存性 [领域依存关系]double insertion 交互中插double-base 双基downgrading 降级dummy 虚位duration 音长{ 学}/时段{语法学/语意学}dynamic programming 动态规划earley algorithm earley 算法echo 回声句egressive 呼气音ejective 紧喉音electronic dictionary 电子词典elementary string 根本字符串 [根本单词串] ellipsis 省略em algorithm em算法embedding 崁入emic 功能关系的empirici 经验论empty category principle 虚范畴原那么 [空范畴原理] empty word 虚词enclitics 后接成份end user 终端用户 [最终用户]endo ntric 同心的endophora 语境照应entailment 蕴涵entity 实体entropy 熵entry 条目episodic memory 情节性记忆epistemological work 认识论网络ergative verb 作格动词ergativity 作格性esperando 世界语etic 无功能关系etymology 词源学eventevent driven control 驱动型控制example-based chine translation 以例句为本的机器翻译excla tion 感慨exclusive disjunction 排它性逻辑“或”experien r case 经验者格expert system 专家系统extension 外延external argument 域外论元extraposition 移外变形 [外置转换]facility value 易度值feature 特征feature bundle 特征束feature co-ourren restriction 特征同现限制 [特性同现限制] feature instantiation 特征表达feature structure 特征结构 [特性结构]feature unification 特征连并 [特性合一]feedback 回馈felicity condition 妥适条件file structure 档案结构finite auto ton 有限状态机 [有限自动机]finite state 有限状态finite state morphology 有限状态构词法 [有限状态词法] finite-state auto ta 有限状态自动机finite-state language 有限状态语言finite-state chine 有限状态机finite-state transdu r 有限状态置换器flap 闪音flat 降音foreground infor tion 前景讯息 [前景信息]for l language theory 形式语言理论for l linguistics 形式语言学for l se ntics 形式语意学forward inferen 前向推理 [向前推理]forward-backward algorithm 前前后后算法frame 框架frame based knowledge representation 框架型知识表示frame theory 框架理论free morpheme 自由语素fregean principle fregean 原那么fricative 擦音f-structure 功能结构full text searching 全文检索function word 功能词functional gram r 功能语法functional programming 函数型程序设计 [函数型程序设计] functional senten perspective 功能句子观functional structure 功能结构functional unification 功能连并 [功能合一]functor 功能符fundamental frequency 基频garden path senten 花园路径句gb (gover ent and binding) 管辖约束geminate 重叠音gender 性generalized phrase structure gram r 概化词组结构语法 [广义短语结构语法]generative gram r 衍生语法generative linguistics 衍生语言学 [生成语言学]generic 泛指geic epistemology 发生认识论geive rker 属格标记genitive 属格gerund 动名词gover ent and binding theory 管辖约束理论gpsg (generalized phrase structure gram r) 概化词组结构语法[广义短语结构语法]gradability 可分级性gram r checker 文法检查器gram tical affix 语法词缀gram tical category 语法范畴gram tical function 语能gram tical inferen 文法推论gram tical relation 语法关系grapheme 字素haplology 类音删略head 中心语head driven phrase structure 中心语驱动词组结构 [中心词驱动词组结构]head feature convention 中心语特征继承原理 [中心词特性继承原理]head-driven phrase structure gram r 中心语驱动词组结构律heteronym 同形heuristic parsing 经验式句法剖析heuristics 经验知识hidden rkov model 隐式马可夫模型hierarchical structure 阶层结构 [层次结构]holophrase 单词句homograph 同形异义词homonym 同音异义词homophone 同音词homophony 同音异义homorganic 同部位音的horn clause horn 子句hpsg (head-driven phrase structure gram r) 中心语驱动词组结构语法hu n- chine inte 人机界面hypernym 上位词hypertext 超文件 [超文本]hyponym 下位词hypotactic 主从结构的ic (immediate constituent) 直接成份icg (infor tion-based case gram r) 讯息为本的格位语法idiom 成语 [熟语]idiosyncrasy 特异性illocutionary 施为性immediate constituent 直接成份imperative 祈使句implicative predicate 蕴含谓词implicature 含意indexical 标引的indirect object 间接宾语indirect speech act 间接言谈行动 [间接言语行为] indo-european language 印欧语言inductional inferen 归纳推理inferen chine 推理机器infinitive 不定词 [to 不定式]infix 中缀inflection/inflexion 屈折变化inflectional affix 屈折词缀infor tion extraction 信息撷取infor tion pro ssing 信息处理 [信息处理]infor tion retrieval 信息检索infor tion scien 信息科学 [信息科学; 情报科学] infor tion theory 信息论 [信息论]inherent feature 固有特征inherit 继承inheritan 继承inheritan hierarchy 继承阶层 [继承层次]inheritan of attribute 属性继承innateness position 语法天生假说insertion 中插inside-outside algorithm 里里外外算法instantiation 表达instrumental (case) 工具格integrated parser 集成句法剖析程序integrated theory of discourse ysis 篇章分析综合理论 [言谈分析综合理论]in igen intensive production 知识密集型生产intensifier 加强成分intensional logic 内含逻辑intensional se ntics 内涵语意学intensional type 内含类型interjection/excla tion 感慨词inter-level 中间成分interlingua 中介语言interlingual 中介语(的）interlocutor 对话者internalise 内化international phoic association (ipa) 国际学会inter 网际网络interpretive se ntics 诠释性语意学intonation 语调intonation unit (iu) 语调单位ipa (international phoic association) 国际学会ir (infor tion retrieval) 信息检索is-a relation is-a 关系isomorphi 同形现象iu (intonation unit) 语调单位junction 连接keyword in context 上下文中关键词[上下文内关键词] kinesics 体势学knowledge acquisition 知识习得knowledge base 知识库knowledge based chine translation 知识为本之机器翻译knowledge extraction 知识撷取 [知识题取]knowledge representation 知识表示kwic (keyword in context) 关键词前后文 [上下文内关键词] label 卷标labial 唇音labio-dental 唇齿音labio-velar 软颚唇音lad (language acquisition devi ) 语言习得装置lag 发声延迟language acquisition 语言习得language acquisition devi 语言习得装置language engineering 语言工程language generation 语言生成language intuition 语感language model 语言模型language technology 语言科技left-corner parsing 左角落剖析 [左角句法剖析] lem 词元lenis 弱辅音letter-to-phone 字转音lexeme 词汇单位lexical ambiguity 词汇歧义lexical category 词类lexical con ptual structure 词汇概念结构lexical entry 词项lexical entry selection standard 选词标准lexical integrity 词语完整性lexical se ntics 词汇语意学lexical-functional gram r 词汇功能语法lexicography 词典学lexicology 词汇学lexicon 词汇库 [词典;词库]lexis 词汇层lf (logical form) 逻辑形式lfg (lexical-functional gram r) 词汇功能语法liaison 连音linear bounded auto ton 线性有限自主机linear pre den 线性次序lingua franca 共通语linguistic decoding 语言译码linguistic unit 语言单位linked list 串行loan 外来语local 局部的locali 方位主义localizer 方位词locus model 轨迹模型locution 惯用语logic 逻辑logic array work 逻辑数组网络logic programming 逻辑程序设计 [逻辑程序设计] logical form 逻辑形式logical operator 逻辑算子 [逻辑算符]logic-based gram r 逻辑为本语法 [基于逻辑的语法] long term memory 记忆longest tch principle 最长匹配原那么 [最长一致法] lr (left-right) parsing lr 剖析chine dictionary 机器词典chine language 机器语言chine learning 机器学习chine translation 机器翻译chine-readable dictionary (mrd) 机读辞典crolinguistics 宏观语言学rkov chart 马可夫图the tical linguistics 数理语言学ximum entropy 最大熵m-d (modifier-head) construction 偏正结构mean length of utteran (mlu) 语句平均长度measure of infor tion 讯习测度 [信息测度] memory based 根据记忆的mental lexicon 心理词汇库mental model 心理模型mental pro ss 心理过程 [智力过程;智力处理] metalanguage 超语言metaphor 隐喻metaphorical extension 隐喻扩展metarule 律上律 [元规那么]metathesis 易位microlinguistics 微观语言学middle structure 中间式结构mini l pair 最小对mini list program 微言主义mlu (mean length of utteran ) 语句平均长度modal 情态词modal auxiliary 情态助动词modal logic 情态逻辑modifier 修饰语modular logic gram r 模块化逻辑语法modular parsing system 模块化句法剖析系统modularity 模块性(理论)module 模块monophthong 单元音monotonic 单调monotonicity 单调性montague gram r 蒙泰究语法 [蒙塔格语法] mood 语气morpheme 词素morphological affix 构词词缀morphological deposition 语素分解morphological pattern 词型morphological pro ssing 词素处理morphological rule 构词律 [词法规那么] morphological segmentation 语素切分morphology 构词学morphophonemics 词音学 [形态音位学;语素音位学] morphophonological rule 形态音位规那么morphosyntax 词句法motor theory 肌动理论movement 移位mrd ( chine-readable dictionary) 机读辞典模板,内容仅供参考。
基础研究好的英文sci题目Fundamental Research: The Foundation for Groundbreaking DiscoveriesThe pursuit of scientific knowledge has always been a driving force behind human progress and innovation. At the heart of this endeavor lies fundamental research, a critical component that lays the groundwork for groundbreaking discoveries and technological advancements. In the realm of science, the exploration of the unknown and the seeking of deeper understanding are the primary motivations that propel us forward, and it is through fundamental research that we uncover the insights and principles that shape our understanding of the world around us.Fundamental research is the systematic investigation of the underlying principles and phenomena that govern our universe. It is the exploration of the unknown, the pursuit of knowledge for the sake of knowledge itself, without the immediate goal of practical application. This type of research is often driven by curiosity and the innate human desire to understand the world in which we live. It is the foundation upon which all scientific progress is built, as it provides the essential building blocks of knowledge that can then beapplied to solve real-world problems.One of the key aspects of fundamental research is its potential for serendipitous discovery. When scientists embark on the journey of exploring the unknown, they often stumble upon unexpected findings that can lead to transformative breakthroughs. These discoveries, made while investigating seemingly unrelated phenomena, have the power to revolutionize our understanding of the world and open up new avenues for further research and development.A prime example of the impact of fundamental research is the discovery of X-rays by Wilhelm Röntgen in 1895. Röntgen was conducting experiments on cathode ray tubes when he observed that a nearby fluorescent screen was emitting a previously unknown type of radiation. This chance observation, made during the course of his fundamental research, led to the discovery of X-rays, which have since become an invaluable tool in fields ranging from medical imaging to materials science.Similarly, the development of quantum mechanics, a foundational theory in modern physics, was the result of decades of fundamental research into the behavior of subatomic particles. The work of physicists like Niels Bohr, Werner Heisenberg, and Erwin Schrödinger, who sought to understand the fundamental nature of matter andenergy, laid the groundwork for the revolutionary concepts that underpin our modern understanding of the physical world.Beyond these landmark discoveries, fundamental research has also contributed to a myriad of other scientific advancements that have transformed our lives. From the development of the internet and the World Wide Web, which grew out of the fundamental research in computer science and telecommunications, to the breakthroughs in biotechnology and medicine that have saved countless lives, the impact of fundamental research is far-reaching and profound.It is important to recognize that the value of fundamental research is not always immediately apparent. The practical applications and real-world implications of a particular line of research may not be immediately evident, and it may take years or even decades before the full significance of a discovery is realized. This is why it is crucial for society to maintain a strong commitment to funding and supporting fundamental research, even in the face of short-term pressures for more applied or commercially-oriented research.By investing in fundamental research, we are not only expanding the frontiers of human knowledge but also laying the groundwork for future innovations that can transform our world. It is through this sustained exploration of the unknown that we uncover the insights and principles that will drive the next generation of technologicaland scientific breakthroughs.In conclusion, fundamental research is the bedrock upon which all scientific progress is built. It is the tireless pursuit of knowledge for the sake of knowledge, the exploration of the unknown that leads to transformative discoveries and advancements. By maintaining a robust and well-funded ecosystem of fundamental research, we can continue to push the boundaries of human understanding and unlock the secrets of our universe, ultimately paving the way for a better future for all.。
华中科技大学本科专业人材培养计划电气工程及其自动化专业本科培养计划Undergraduate Program for Specialty in Electrical EngineeringAa tdomation一、培养目标Ⅰ . Educational Objectives培养德、智、体全面发展，知识、能力、素质协调发展，能够从事与电气工程有关的系统设计、运行控制、信息处理、研究开辟以及电子计算机应用等领域工作的宽口径、复合型高级技术人材。
This program nurtures high-quality technical talents with a broad adaptability,capabilities of such job fields related to electrical engineering, including system designing, operation controlling, information processing, researching and developing, and computer applications.二、基本规格要求Ⅱ . Skills Profile本专业学生主要学习电工技术、电子技术、信号处理、自动控制、计算机技术、机电学、电力电子技术、电气工程基础等电气工程技术基础和专业知识，并接受1~2 个学科专业方向的基本训练，具有分析解决电气工程与控制技术问题的能力。
毕业生应获得以下几个方面的知识和能力：1.扎实的数理基础，较好的人文社会科学和管理科学基础，以及外语综合能力；2.系统掌握本学科领域必需的技术基础理论知识，包括电路理论、电子技术、信号与系统、自动控制理论、计算机软硬件、机电学、电力电子学、电气工程基础等。
3.较强的工程实践能力，较熟练的计算机应用能力；4.本学科领域内1~2 个专业方向的知识与技能，了解本学科前沿的发展趋势；5.较强的工作适应能力，一定的科学研究、技术开辟和组织管理的实际工作能力。
阿基米德蜗杆Archimedes worm安全系数safety factor;factor of safety安全载荷safe load凹面、凹度concavity扳手wrench板簧flat leafspring半圆键woodruff key变形deformation摆杆oscillating bar摆动从动件oscillating follower摆动从动件凸轮机构cam with oscillati ng follower摆动导杆机构oscillating guide-bar me chanism摆线齿轮cycloidal gear摆线齿形cycloidal tooth profile摆线运动规律cycloidal motion摆线针轮cycloidal-pin wheel包角angle of contact保持架cage背对背安装back-to-back arrangement背锥back cone ；normal cone背锥角back angle背锥距back cone distance 比例尺scale比热容specific heat capacity 闭式链closed kinematic chain 闭链机构closed chain mechanism 臂部arm变频器frequency converters 变频调速frequency control of motor speed变速speed change变速齿轮change gear ; change wheel 变位齿轮modified gear变位系数modification coefficient 标准齿轮standard gear标准直齿轮standard spur gear 表面质量系数superficial mass factor 表面传热系数surface coefficient of heat transfer表面粗糙度surface roughness 并联式组合combination in parallel 并联机构parallel mechanism 并联组合机构parallel combined mechanism并行工程concurrent engineering 并行设计concurred design, CD 不平衡相位phase angle of unbalance 不平衡imbalance (or unbalance)不平衡量amount of unbalance 不完全齿轮机构intermittent gearing 波发生器wave generator波数number of waves补偿compensation参数化设计parameterization design,PD残余应力residual stress操纵及控制装置operation control device槽轮Geneva wheel槽轮机构Geneva mechanism ；Maltese c ross槽数Geneva numerate槽凸轮groove cam侧隙backlash差动轮系differential gear train差动螺旋机构differential screw mecha nism差速器differential常用机构conventional mechanism; mech anism in common use车床lathe承载量系数bearing capacity factor承载能力bearing capacity成对安装paired mounting尺寸系列dimension series齿槽tooth space齿槽宽spacewidth齿侧间隙backlash齿顶高addendum齿顶圆addendum circle齿根高dedendum齿根圆dedendum circle齿厚tooth thickness齿距circular pitch齿宽face width齿廓tooth profile齿廓曲线tooth curve 齿轮gear齿轮变速箱speed-changing gear boxes 齿轮齿条机构pinion and rack 齿轮插刀pinion cutter; pinion-shaped shaper cutter齿轮滚刀hob ,hobbing cutter 齿轮机构gear齿轮轮坯blank齿轮传动系pinion unit齿轮联轴器gear coupling齿条传动rack gear齿数tooth number齿数比gear ratio齿条rack齿条插刀rack cutter; rack-shaped shaper cutter齿形链、无声链silent chain 齿形系数form factor齿式棘轮机构tooth ratchet mechanism 插齿机gear shaper重合点coincident points重合度contact ratio冲床punch传动比transmission ratio,speed ratio传动装置gearing; transmission gear 传动系统driven system传动角transmission angle传动轴transmission shaft串联式组合combination in series 串联式组合机构series combined mechanism串级调速cascade speed control创新innovation ; creation创新设计creation design垂直载荷、法向载荷normal load唇形橡胶密封lip rubber seal磁流体轴承magnetic fluid bearing 从动带轮driven pulley从动件driven link, follower从动件平底宽度width of flat-face 从动件停歇follower dwell从动件运动规律follower motion从动轮driven gear粗线bold line粗牙螺纹coarse thread大齿轮gear wheel打包机packer打滑slipping带传动belt driving带轮belt pulley带式制动器band brake单列轴承single row bearing单向推力轴承single-direction thrust bearing单万向联轴节single universal joint 单位矢量unit vector当量齿轮equivalent spur gear;virtual gear当量齿数equivalent teeth number;virtual number of teeth当量摩擦系数equivalent coefficientof friction当量载荷equivalent load 刀具cutter导数derivative倒角chamfer导热性conduction of heat导程lead导程角lead angle等加等减速运动规律parabolic motion;constant acceleration anddeceleration motion等速运动规律uniform motion; constant velocity motion等径凸轮conjugate yoke radial cam 等宽凸轮constant-breadth cam 等效构件equivalent link等效力equivalent force等效力矩equivalent moment of force 等效量equivalent等效质量equivalent mass等效转动惯量equivalent moment of inertia等效动力学模型dynamically equivalent model底座chassis低副lower pair点划线chain dotted line（疲劳）点蚀pitting垫圈gasket垫片xx gasket seal碟形弹簧belleville spring顶隙bottom clearance定轴轮系ordinary gear train; gear train with fixed axes 动力学dynamics动密封kinematical seal动能dynamic energy动力粘度dynamic viscosity动力润滑dynamic lubrication动平衡dynamic balance动平衡机dynamic balancing machine动态特性dynamic characteristics动态分析设计dynamic analysis design动压力dynamic reaction动载荷dynamic load端面transverse plane端面参数transverse parameters端面齿距transverse circular pitch端面齿廓transverse tooth profile端面重合度transverse contact ratio端面模数transverse module端面压力角transverse pressure angle锻造forge对称循环应力symmetry circulating stress对心滚子从动件radial (or in-line )roller follower对心直动从动件radial (or in-line )translating follower对心移动从动件radial reciprocatingfollower对心曲柄滑块机构in-line slider-crank(or crank-slider) mechanism多列轴承multi-row bearing多楔带poly V-belt多项式运动规律polynomial motion多质量转子rotor with several masses 惰轮idle gear额定寿命rating life额定载荷load ratingII 级杆组dyad发生线generating line发生面generating plane法面normal plane法面参数normal parameters法面齿距normal circular pitch 法面模数normal module法面压力角normal pressure angle 法向齿距normal pitch法向齿廓normal tooth profile 法向直廓蜗杆straight sided normal worm法向力normal force反馈式组合feedback combining 反向运动学inverse ( or backward)kinematics反转法kinematic inversion反正切Arctan范成法generating cutting仿形法form cutting方案设计、概念设计concept design, CD 防振装置shockproof device 飞轮flywheel飞轮矩moment of flywheel非标准齿轮nonstandard gear 非接触式密封non-contact seal 非周期性速度波动aperiodic speed fluctuation非圆齿轮non-circular gear粉末合金powder metallurgy分度线reference line; standard pitchline分度圆reference circle; standard (cutting) pitch circle分度圆柱导程角lead angle at reference cylinder 分度圆柱螺旋角helixangle at reference cylinder分母denominator分子numerator分度圆锥reference cone; standardpitch cone分析法analytical method封闭差动轮系planetary differential复合铰链compound hinge复合式组合compound combining复合轮系compound (or combined) gear train复合平带compound flat belt复合应力combined stress复式螺旋机构Compound screw mechanism复杂机构complex mechanism杆组Assur group干涉interference刚度系数stiffness coefficient刚轮rigid circular spline钢丝软轴wire soft shaft刚体导引机构body guidance mechanism刚性冲击rigid impulse (shock)刚性转子rigid rotor刚性轴承rigid bearing刚性联轴器rigid coupling高度系列height series高速带high speed belt高副higher pair 格拉晓夫定理Grashoff`s law 根切undercutting公称直径nominal diameter高度系列height series功work工况系数application factor 工艺设计technological design 工作循环图working cycle diagram 工作机构operation mechanism 工作载荷external loads工作空间working space工作应力working stress工作阻力effective resistance 工作阻力矩effective resistance moment 公法线common normal line公共约束general constraint 公制齿轮metric gears功率power功能分析设计function analyses design 共轭齿廓conjugate profiles 共轭凸轮conjugate cam构件link鼓风机blower固定构件fixed link; frame固体润滑剂solid lubricant关节型操作器jointed manipulator 惯性力inertia force惯性力矩moment of inertia ,shaking moment 惯性力平衡balance of shaking force 惯性力完全平衡full balance of shaking force 惯性力部分平衡partial balance of shaking force 惯性主矩resultant moment of inertia 惯性主失resultant vector of inertia 冠轮crown gear广义机构generation mechanism广义坐标generalized coordinate轨迹生成path generation轨迹发生器path generator滚刀hob滚道raceway滚动体rolling element滚动轴承rolling bearing滚动轴承代号rolling bearing identifi cation code滚针needle roller滚针轴承needle roller bearing滚子roller滚子轴承roller bearing滚子半径radius of roller滚子从动件roller follower滚子链roller chain滚子链联轴器double roller chain coup ling滚珠丝杆ball screw滚柱式单向超越离合器roller clutch 过度切割undercutting函数发生器function generator函数生成function generation含油轴承oil bearing耗油量oil consumption耗油量系数oil consumption factor赫兹公式H. Hertz equation合成弯矩resultant bending moment合力resultant force合力矩resultant moment of force 黑箱black box横坐标abscissa互换性齿轮interchangeable gears 花键spline滑键、导键feather key滑动轴承sliding bearing滑动率sliding ratio滑块slider环面蜗杆toroid helicoids worm 环形弹簧annular spring缓冲装置shocks; shock-absorber 灰铸铁grey cast iron回程return回转体平衡balance of rotors 混合轮系compound gear train 积分integrate机电一体化系统设计mechanical-electrical integration system design 机构mechanism机构分析analysis of mechanism 机构平衡balance of mechanism 机构学mechanism机构运动设计kinematic design of mechanism机构运动简图kinematic sketch of mechanism机构综合synthesis of mechanism 机构组成constitution of mechanism 机架frame, fixed link机架变换kinematic inversion 机器machine机器人robot机器人操作器manipulator机器人学robotics技术过程technique process技术经济评价technical and economic evaluation技术系统technique system机械machinery机械创新设计mechanical creation design, MCD机械系统设计mechanical system design,MSD机械动力分析dynamic analysis of machinery机械动力设计dynamic design of machinery机械动力学dynamics of machinery机械的现代设计modern machine design机械系统mechanical system机械利益mechanical advantage机械平衡balance of machinery机械手manipulator机械设计machine design; mechanical design机械特性mechanical behavior机械调速mechanical speed governors机械效率mechanical efficiency机械原理theory of machines and mechanisms机械运转不均匀系数coefficient of speed fluctuation机械无级变速mechanical stepless speed changes基础机构fundamental mechanism基本额定寿命basic rating life 基于实例设计case-based design,CBD 基圆base circle基圆半径radius of base circle 基圆齿距base pitch基圆压力角pressure angle of base circle基圆柱base cylinder基圆锥base cone急回机构quick-return mechanism 急回特性quick-return characteristics 急回系数advance-to return-time ratio 急回运动quick-return motion 棘轮ratchet棘轮机构ratchet mechanism棘爪pawl极限位置extreme (or limiting) position极位夹角crank angle between extreme (or limiting) positions计算机辅助设计computer aided design, CAD计算机辅助制造computer aided manufacturing, CAM计算机集成制造系统computer integrated manufacturing system, CIMS 计算力矩factored moment; calculation moment计算弯矩calculated bending moment 加权系数weighting efficient 加速度acceleration加速度分析acceleration analysis 加速度曲线acceleration diagram 尖点pointing; cusp尖底从动件knife-edge follower间隙backlash间歇运动机构intermittent motion mechanism减速比reduction ratio减速齿轮、减速装置reduction gear减速器speed reducer减摩性anti-friction quality渐开螺旋面involute helicoid渐开线involute渐开线齿廓involute profile渐开线齿轮involute gear渐开线发生线generating line of invol ute渐开线方程involute equation渐开线函数involute function渐开线蜗杆involute worm渐开线压力角pressure angle ofinvolute渐开线花键involute spline简谐运动simple harmonic motion键key键槽keyway交变应力repeated stress交变载荷repeated fluctuating load 交叉带传动cross-belt drive交错轴斜齿轮crossed helical gears胶合scoring角加速度angular acceleration角速度angular velocity角速比angular velocity ratio角接触球轴承angular contact ballbearing 角接触推力轴承angular contact thrust bearing 角接触向心轴承angular contact radial bearing角接触轴承angular contact bearing 铰链、枢纽hinge校正平面correcting plane接触应力contact stress接触式xx contact seal阶梯轴multi-diameter shaft 结构structure结构设计structural design截面section节点pitch point节距circular pitch; pitch of teeth 节线pitch line节圆pitch circle节圆齿厚thickness on pitch circle 节圆直径pitch diameter节圆锥pitch cone节圆锥角pitch cone angle解析设计analytical design紧边tight-side紧固件fastener径节diametral pitch径向radial direction径向当量动载荷dynamic equivalent radial load径向当量静载荷static equivalent radial load径向基本额定动载荷basic dynamic radial load rating 径向基本额定静载荷basic static radial load tating径向接触轴承radial contact bearing径向平面radial plane径向游隙radial internal clearance径向载荷radial load径向载荷系数radial load factor径向间隙clearance静力static forcexx static balancexx载荷static loadxxxx static seal局部自由度passive degree of freedom矩阵matrix矩形螺纹square threaded form锯齿形螺纹buttress thread form矩形牙嵌式离合器square-jaw positive-contact clutch绝对尺寸系数absolute dimensional factor绝对运动absolute motion绝对速度absolute velocity均衡装置load balancing mechanism抗压强度compression strength开口传动open-belt drive开式链open kinematic chain开链机构open chain mechanism可靠度degree of reliability可靠性reliability可靠性设计reliability design, RD空气弹簧air spring空间机构spatial mechanism空间连杆机构spatial linkage空间凸轮机构spatial cam 空间运动副spatial kinematic pair 空间运动链spatial kinematic chain 空转idle宽度系列width series框图block diagram雷诺方程Reynolds‘s equation 离心力centrifugal force离心应力centrifugal stress 离合器clutch离心密封centrifugal seal理论xx pitch curve理论啮合线theoretical line of action 隶属度membership力force力多边形force polygon力封闭型凸轮机构force-drive (or force-closed) cam mechanism 力矩moment力平衡equilibrium力偶couple力偶矩moment of couple连杆connecting rod, coupler 连杆机构linkage连杆曲线coupler-curve连心线line of centers链chain链传动装置chain gearing链轮sprocket ; sprocket-wheel ; sprocket gear ; chain wheel联组V 带tight-up V belt联轴器coupling ; shaft coupling 两维凸轮two-dimensional cam 临界转速critical speed六杆机构six-bar linkage龙门刨床double Haas planer轮坯blank轮系gear train螺杆screw螺距thread pitch螺母screw nut螺旋锥齿轮helical bevel gear螺钉screws螺栓bolts螺纹导程lead螺纹效率screw efficiency螺旋传动power screw螺旋xx spiral seal螺纹thread (of a screw)螺旋副helical pair螺旋机构screw mechanism螺旋角helix angle螺旋线helix ,helical line绿色设计green design ; design for environment马耳他机构Geneva wheel ; Geneva gear马耳他十字Maltese cross脉动无级变速pulsating stepless speedchanges脉动循环应力fluctuating circulatingstress脉动载荷fluctuating load铆钉rivet迷宫密封labyrinth sealxx sealxx带seal belt密封胶seal gum 密封元件potted component密封装置sealing arrangement 面对面安装face-to-face arrangement 面向产品生命周期设计design for product`s life cycle, DPLC名义应力、公称应力nominal stress 模块化设计modular design, MD 模块式传动系统modular system 模幅箱morphology box模糊集fuzzy set模糊评价fuzzy evaluation模数module摩擦friction摩擦角friction angle摩擦力friction force摩擦学设计tribology design, TD 摩擦阻力frictional resistance 摩擦力矩friction moment摩擦系数coefficient of friction 摩擦圆friction circle磨损abrasion ;wear; scratching 末端执行器end-effector目标函数objective function 耐腐蚀性corrosion resistance 耐磨性wear resistance挠性机构mechanism with flexible elements 挠性转子flexible rotor内齿轮internal gear内齿圈ring gear内力internal force内圈inner ring能量energy能量指示图viscosity逆时针counterclockwise (or anticlockwise)啮出engaging-out啮合engagement, mesh, gearing啮合点contact points啮合角working pressure angle啮合线line of action啮合线长度length of line of action 啮入engaging-in牛头刨床shaper凝固点freezing point; solidifying point扭转应力torsion stress扭矩moment of torque扭簧helical torsion springxx模图NomogramO 形密封圈密封O ring seal盘形凸轮disk cam盘形转子disk-like rotor抛物线运动parabolic motion疲劳极限fatigue limit疲劳强度fatigue strength偏置式offset偏(心)距offset distance偏心率eccentricity ratio偏心质量eccentric mass偏距圆offset circle偏心盘eccentric偏置滚子从动件offset roller follower偏置尖底从动件offset knife-edgefollower 偏置曲柄滑块机构offset slider-crank mechanism 拼接matching评价与决策evaluation and decision 频率frequency平带flat belt平带传动flat belt driving平底从动件flat-face follower 平底宽度face width平分线bisector平均应力average stress平均中径mean screw diameter 平均速度average velocity 平衡balance平衡机balancing machine平衡品质balancing quality平衡平面correcting plane平衡质量balancing mass平衡重counterweight平衡转速balancing speed平面副planar pair, flat pair 平面机构planar mechanism平面运动副planar kinematic pair 平面连杆机构planar linkage 平面凸轮planar cam平面凸轮机构planar cam mechanism 平面轴斜齿轮parallel helical gears 普通平键parallel key其他常用机构other mechanism in common use起动阶段starting period启动力矩starting torque气动机构pneumatic mechanism 奇异位置singular position起始啮合点initial contact ,beginningof contact气体轴承gas bearing千斤顶jack嵌入键sunk key强迫振动forced vibration切齿xx depth of cut曲柄crank曲柄存在条件Grashoff`s law曲柄导杆机构crank shaper (guide-bar)mechanism曲柄滑块机构slider-crank (or crank-slider) mechanism曲柄摇杆机构crank-rocker mechanism曲齿锥齿轮spiral bevel gear曲率curvature曲率半径radius of curvature曲面从动件curved-shoe follower曲线拼接curve matching曲线运动curvilinear motion曲轴crank shaft驱动力driving force驱动力矩driving moment (torque)全齿高whole depth权重集weight sets球ball球面滚子convex roller球轴承ball bearing球面副spheric pair球面渐开线spherical involute球面运动spherical motion球销副sphere-pin pair 球坐标操作器polar coordinate manipulator 燃点spontaneous ignition热平衡heat balance; thermal equilibrium人字齿轮herringbone gear冗余自由度redundant degree of freedom 柔轮flexspline柔性冲击flexible impulse; soft shock 柔性制造系统flexible manufacturing system; FMS柔性自动化flexible automation 润滑油膜lubricant film润滑装置lubrication device 润滑lubrication润滑剂lubricant三角形花键serration spline 三角形螺纹V thread screw三维凸轮three-dimensional cam 三心定理Kennedy`s theorem砂轮越程槽grinding wheel groove 砂漏hour-glass少齿差行星传动planetary drive with small teeth difference设计方法学design methodology 设计变量design variable设计约束design constraints 深沟球轴承deep groove ball bearing 生产阻力productive resistance 升程rise升距lift实际xx cam profile十字滑块联轴器double slider coupling;Oldham‘s coupling矢量vector输出功output work输出构件output link输出机构output mechanism输出力矩output torque输出轴output shaft输入构件input link数学模型mathematic model实际啮合线actual line of action双滑块机构double-slider mechanism, ellipsograph双曲柄机构double crank mechanism 双曲面齿轮hyperboloid gear双头螺柱studs双万向联轴节constant-velocity (or do uble) universal joint双摇杆机构double rocker mechanism 双转块机构Oldham coupling双列轴承double row bearing双向推力轴承double-direction thrust bearingxx slack-side顺时针clockwise瞬心instantaneous center死点dead point四杆机构four-bar linkage速度velocity速度不均匀(波动)系数coefficientof speed fluctuation速度波动speed fluctuation速度曲线velocity diagram 速度瞬心instantaneous center of velocity塔轮step pulley踏板pedal台钳、虎钳vicexx轮sun gear弹性滑动elasticity sliding motion 弹性联轴器elastic coupling ; flexible coupling弹性套柱销联轴器rubber-cushioned sleeve bearing coupling套筒sleeve梯形螺纹acme thread form特殊运动链special kinematic chain 特性characteristics替代机构equivalent mechanism 调节modulation, regulation 调心滚子轴承self-aligning roller bearing调心球轴承self-aligning ball bearing 调心轴承self-aligning bearing 调速speed governing调速电动机adjustable speed motors 调速系统speed control system 调压调速variable voltage control 调速器regulator, governor铁磁流体密封ferrofluid seal 停车阶段stopping phase停歇dwell同步带synchronous belt同步带传动synchronous belt drive 凸的，凸面体convex 凸轮cam凸轮倒置机构inverse cam mechanism凸轮机构cam , cam mechanism凸xx cam profile凸轮廓线绘制layout of cam profile凸轮理论xx pitch curve凸缘联轴器flange coupling图册、图谱atlas图解法graphical method推程rise推力球轴承thrust ball bearing推力轴承thrust bearing退刀槽tool withdrawal groove退火anneal陀螺仪gyroscopeV 带V belt外力external force外圈outer ring外形尺寸boundary dimension万向联轴器Hooks coupling ; universalcoupling外齿轮external gear弯曲应力beading stress弯矩bending moment腕部wrist往复移动reciprocating motion往复式密封reciprocating seal网上设计on-net design, OND微动螺旋机构differential screw mechanism位移displacement位移曲线displacement diagram位姿pose , position and orientation稳定运转阶段steady motion period 稳健设计robust design 蜗杆worm蜗杆传动机构worm gearing蜗杆头数number of threads蜗杆直径系数diametral quotient 蜗杆蜗轮机构worm and worm gear 蜗杆形凸轮步进机构worm cam interval mechanism蜗杆旋向hands of worm蜗轮worm gear涡圈形盘簧power spring无级变速装置stepless speed changes devices无穷大infinite系杆crank arm, planet carrier 现场平衡field balancing向心轴承radial bearing向心力centrifugal force相对速度relative velocity相对运动relative motion相对间隙relative gap象限quadrant橡皮泥plasticine细牙螺纹fine threads销pin消耗consumption小齿轮pinion小径minor diameter橡胶弹簧balata spring修正梯形加速度运动规律modified trapezoidal acceleration motion 修正正弦加速度运动规律modified sine acceleration motion斜齿圆柱齿轮helical gear斜键、钩头楔键taper key泄漏leakage谐波齿轮harmonic gear谐波传动harmonic driving谐波发生器harmonic generator斜齿轮的当量直齿轮equivalent spur gear of the helical gear心轴spindle行程速度变化系数coefficient of travel speed variation行程速比系数advance-to return-time ratio行星齿轮装置planetary transmission行星轮planet gear行星轮变速装置planetary speed changing devices行星轮系planetary gear train形封闭凸轮机构positive-drive (or form-closed) cam mechanism虚拟现实virtual reality虚拟现实技术virtual reality technology, VRT虚拟现实设计virtual reality design,VRD虚约束redundant (or passive) constraint许用不平衡量allowable amount of unbalance许用压力角allowable pressure angle许用应力allowable stress; permissible stress悬臂结构cantilever structure 悬臂梁cantilever beam循环功率流circulating power load 旋转力矩running torque 旋转式密封rotating seal旋转运动rotary motion选型type selection压力pressure压力中心center of pressure 压缩机compressor压应力compressive stress压力角pressure angle牙嵌式联轴器jaw (teeth) positive-contact coupling雅可比矩阵Jacobi matrix摇杆rocker液力传动hydrodynamic drive 液力耦合器hydraulic couplers 液体弹簧liquid spring液压无级变速hydraulic stepless speed changes液压机构hydraulic mechanism 一般化运动链generalized kinematic chain移动从动件reciprocating follower 移动副prismatic pair, sliding pair 移动关节prismatic joint移动凸轮wedge cam盈亏功increment or decrement work 应力幅stress amplitude应力集中stress concentration 应力集中系数factor of stress concentration应力图stress diagram应力—应变图stress-strain diagram优化设计optimal design油杯oil bottle油壶oil can油沟密封oily ditch seal有害阻力useless resistance有益阻力useful resistance有效拉力effective tension有效圆周力effective circle force有害阻力detrimental resistance余弦加速度运动cosine acceleration (o r simple harmonic) motion预紧力preload原动机primer mover圆带round belt圆带传动round belt drive圆弧齿厚circular thickness圆弧圆柱蜗杆hollow flank worm圆角半径fillet radius圆盘摩擦离合器disc friction clutch圆盘制动器disc brake原动机prime mover原始机构original mechanism圆形齿轮circular gear圆柱滚子cylindrical roller圆柱滚子轴承cylindrical roller bearing 圆柱副cylindric pair圆柱式凸轮步进运动机构barrel (cylindric) cam圆柱螺旋拉伸弹簧cylindroid helical-coil extension spring圆柱螺旋扭转弹簧cylindroid helical-coil torsion spring 圆柱螺旋压缩弹簧cylindroid helical-coil compression spring 圆柱凸轮cylindrical cam圆柱蜗杆cylindrical worm圆柱坐标操作器cylindrical coordinate manipulator圆锥螺旋扭转弹簧conoid helical-coil compression spring圆锥滚子tapered roller圆锥滚子轴承tapered roller bearing 圆锥齿轮机构bevel gears圆锥角cone angle原动件driving link约束constraint约束条件constraint condition 约束反力constraining force 跃度jerkxx曲线jerk diagram运动倒置kinematic inversion 运动方案设计kinematic precept design 运动分析kinematic analysis 运动副kinematic pair运动构件moving link运动简图kinematic sketch运动链kinematic chain运动失真undercutting运动设计kinematic design运动周期cycle of motion运动综合kinematic synthesis 运转不均匀系数coefficient of velocity fluctuation运动粘度kenematic viscosity 载荷load载荷—变形曲线load—deformation curve载荷—变形图load—deformation diagram窄V 带narrow V belt毡圈密封felt ring seal展成法generating张紧力tension张紧轮tension pulley振动vibration振动力矩shaking couple振动频率frequency of vibration振幅amplitude of vibration正切机构tangent mechanism正向运动学direct (forward) kinematics正弦机构sine generator, scotch yoke织布机loom正应力、法向应力normal stress制动器brake直齿圆柱齿轮spur gear直齿锥齿轮straight bevel gear直角三角形right triangle直角坐标操作器Cartesian coordinate manipulator直径系数diametral quotient直径系列diameter series直廓环面蜗杆hindley worm直线运动linear motion直轴straight shaft质量mass质心center of mass执行构件executive link; working link质径积mass-radius product智能化设计intelligent design, ID中间平面mid-plane 中心距center distance中心距变动center distance change 中心轮central gear 中径mean diameter终止啮合点final contact, end of contact周节pitch周期性速度波动periodic speed fluctuation周转轮系epicyclic gear train 肘形机构toggle mechanism轴shaft轴承盖bearing cup轴承合金bearing alloy轴承座bearing block轴承高度bearing height轴承宽度bearing width轴承内径bearing bore diameter 轴承寿命bearing life轴承套圈bearing ring轴承外径bearing outside diameter 轴颈journal轴瓦、轴承衬bearing bush轴端挡圈shaft end ring轴环shaft collar轴肩shaft shoulder轴角shaft angle轴向axial direction轴向齿廓axial tooth profile 轴向当量动载荷dynamic equivalent axial load 轴向当量静载荷static equivalent axial load轴向基本额定动载荷basic dynamic axial load rating轴向基本额定静载荷basic static axial load rating轴向接触轴承axial contact bearing 轴向平面axial plane主动件driving link主动齿轮driving gear主动带轮driving pulley转动导杆机构whitworth mechanism 转动副revolute (turning) pair转速swiveling speed ; rotating speed 转动关节revolute joint转轴revolving shaft转子rotor转子平衡balance of rotor装配条件assembly condition锥齿轮bevel gear锥顶common apex of cone锥距cone distance锥轮bevel pulley; bevel wheel锥齿轮的当量直齿轮equivalent spurgear of the bevel gear锥面包络圆柱蜗杆milled helicoids worm准双曲面齿轮hypoid gear子程序subroutine子机构sub-mechanism自动化automation自锁self-locking 轴向游隙axial internal clearance 轴向载荷axial load轴向载荷系数axial load factor 轴向分力axial thrust load自锁条件condition of self-locking 自由度degree of freedom, mobility 总重合度total contact ratio 总反力resultant force总效率combined efficiency; overall efficiency组成原理theory of constitution 组合齿形composite tooth form 组合安装stack mounting组合机构combined mechanism 阻抗力resistance最大盈亏功maximum difference work between plus and minus work纵向重合度overlap contact ratio 纵坐标ordinate组合机构combined mechanism 最少齿数minimum teeth number 最小向径minimum radius作用力applied force坐标系coordinate frame。
Fundamental and Technological Limitations of Immersive Audio SystemsCHRIS KYRIAKAKIS,MEMBER,IEEENumerous applications are currently envisioned for immersive audio systems.The principal function of such systems is to synthe-size,manipulate,and render soundfields in real time.In this paper, we examine several fundamental and technological limitations that impede the development of seamless immersive audio sys-tems.Such limitations stem from signal-processing requirements, acoustical considerations,human listening characteristics,and listener movement.We present a brief historical overview to outline the development of immersive audio technologies and discuss the performance and future research directions of immersive audio systems with respect to such st,we present a novel desktop audio system with integrated listener-tracking capability that circumvents several of the technological limitations faced by today’s digital audio workstations.Keywords—Acoustic signal processing,audio systems,auditory system,multimedia systems,signal processing.I.I NTRODUCTIONEmerging integrated media systems seamlessly combine digital video,digital audio,computer animation,text,and graphics into common displays that allow for mixed media creation,dissemination,and interactive access in real time. Immersive audio and video environments based on such systems can be envisioned for applications that include teleconferencing and telepresence;augmented and virtual reality for manufacturing and entertainment;air-traffic con-trol,pilot warning,and guidance systems;displays for the visually or aurally impaired;home entertainment;distance learning;and professional sound and picture editing for television andfilm.The principal function of immersive systems is to synthesize multimodal perceptions that do not exist in the current physical environment,thus immersing users in a seamless blend of visual and aural information. Significant resources have been allocated over the past20 years to promote research in the area of image and video processing,resulting in important advances in thesefields.Manuscript received September8,1997;revised December4,1997.The Guest Editor coordinating the review of this paper and approving it for publication was T.Chen.The author is with the Integrated Media Systems Center,University of Southern California,Los Angeles,CA90089-2564USA(e-mail: ckyriak@).Publisher Item Identifier S0018-9219(98)03283-6.On the other hand,audio signal processing,and particularly immersive audio,have been largely neglected.Accurate spatial reproduction of sound can significantly enhance the visualization of three-dimensional(3-D)infor-mation for applications in which it is important to achieve sound localization relative to visual images.The human ear–brain interface is uniquely capable of localizing and identifying sounds in a3-D environment with remarkable accuracy.For example,human listeners can detect time-of-arrival differences of about7such fundamental limits,and delineation of technological considerations that affect present and future system design and development.In thefinal sections,we will present a novel sound-reproduction system that addresses several of the current technological limitations that currently affect the quality of audio at the desktop.This system incorporates a video-based tracking method that allows real-time process-ing of the audio signal in response to listener movement. II.T HE N ATURE OF L IMITATIONS INI MMERSIVE A UDIO S YSTEMSThere are two classes of limitations that impede the implementation of immersive audio systems.Thefirst class encompasses fundamental limitations that arise from phys-ical laws,and its understanding is essential for determining the feasibility of a particular technology with respect to the absolute physical limits.Many such fundamental limitations are not directly dependent on the choice of systems but instead pertain to the actual process of sound propagation and attenuation in irregularly shaped rooms.The physical properties of the acoustic environment are encoded in the soundfield and must be decoded by an immersive audio system in order to accurately simulate the original envi-ronment.The influence of the local acoustic environment is reflected in the perception of spatial attributes such as direction and distance,as well as in the perception of room spaciousness and source size[1],[2].The situation is further complicated by the fact that the decoding process must include the transformations associated with human hearing.These include the conversion of spatial sound cues into level and time differences and direction-dependent frequency-response effects caused by the pinna,head,and torso through a set of amplitude and phase transformations known as the HRTF’s.The seamless incorporation of such cues in immersive audio systems is a very active area of research that,if successful,will give rise to systems that begin to approach performance near the fundamental limits. The second class of limitations consists of constraints that arise purely from technological considerations.These are equally useful in understanding the potential applications of a given system and are imposed by the particular tech-nology chosen for system implementation.For example, the process of encoding parameters associated with room acoustics into soundfields can be modeled using numerical methods.In theory,this would involve the solution of the wave equation for sound subject to the boundary conditions dictated by the complex(absorptive,reflective, and diffractive)room surfaces.The computational com-plexity of this problem is very high and involves the calculation of estimated10normal modes that fall within the range of human hearing(20Hz–20kHz)for a large hall[4].More recent methods have been developed for rendering soundfields through a process called auralization. Such methods utilize a combination of scaled models, digitalfiltering,and special-purpose hardware for real-time convolution to predict and render the soundfield[5].As the processing power of digital signal processing(DSP)hardware increases,the capability of auralization systems to render complex soundfields will increase proportionally. III.B RIEF H ISTORICAL O VERVIEWA.Two-Channel StereoAlthough many of the principles of stereophonic sound were developed through research efforts in the early1930’s, there still remains a misconception as to the meaning of the word“stereo”itself.While it is generally associated with sound reproduction from two loudspeakers,the word originates from the Greek stereos,meaning solid or three-dimensional.The two-channel association came about in the1950’s because of technological limitations imposed by the phonograph record that had only two groove walls for encoding information.Stereophony started with the work of Blumlein[6]in the United Kingdom,who recognized early on that it was possible to locate a sound within a range of azimuth angles by using an appropriate combination of delay and level differences.His work focused on accurate reproduction of the soundfield at each ear of the listener and on the de-velopment of microphone techniques that would allow the recording of the amplitude and phase differences necessary for stereo reproduction.Fletcher,Steinberg,and Snow at Bell Laboratories in the United States[7]–[9]took a differ-ent approach.They considered a“wall of sound”in which an infinite number of microphones is used to reproduce a soundfield through an infinite number of loudspeakers, similar to the Huygens principle of secondary wavelets. While this made for an interesting theoretical result,the Bell Labs researchers realized that practical implementations would require a significantly smaller number of channels. They showed that a three-channel system consisting of left,center,and right channels in the azimuth plane could represent the lateralization and depth of the desired sound field with acceptable accuracy[Fig.1(a)].Thefirst such stereophonic three-channel system was demonstrated in 1934with the Philadelphia Orchestra performing remotely for an audience in Washington,DC,over wide-band tele-phone lines.B.Four-Channel Matrixed Quadraphonic SystemWhile stereophonic methods can be a powerful tool in the reproduction of the spatial attributes of a sound field,they fall short of true three-dimensional reproduction. The quadraphonic system attempted to circumvent such limitations by capturing and transmitting information about the direct sound and the reverberant soundfield[10],[11]. To deliver the four channels required by quadraphonic recordings over a two-channel medium(e.g.,the phono-graph record),it was necessary to develop an appropriate encoding and decoding scheme.Several such schemes were proposed based on4:2:4matrix encoding/decoding that relied on phase manipulation of the original stereo signals [12].Quadraphonic systems were capable of reproducing sound images fairly accurately in the front and rear sectors942PROCEEDINGS OF THE IEEE,VOL.86,NO.5,MAY1998(a)(b)Fig.1.(a)Stereo was originally invented based on three loud-speakers.Sound images in the center are rendered by a real loudspeaker that delivers the same direct sound to both ears.(b)Inthe two-loudspeaker stereo configuration with a phantom center,the cross-talk terms give rise to a less stable center image as wellas a loss of clarity.of the azimuthal plane,but they exhibited serious limita-tions when attempting to reproduce sound images to the side of the listener.Experiments showed[13],[14]that this was a limitation associated as much with sound-field synthesis using only four channels as with human psychoacoustic mechanisms.These technical limitations and the presence of two competing formats in the consumer marketplace contributed to the early demise of quadraphonic systems.C.Multichannel Surround SoundIn the early1950’s,thefirst multichannel sound format was developed by20th Century Fox.The combination of wide-screen formats such as CinemaScope(35mm) and six-track Todd-AO(70mm)with multichannel sound was thefilm industry’s response to the growing threat of television.Stereophonicfilm sound was typically repro-duced over three front loudspeakers,but these new formats included an additional monophonic channel that was repro-duced over two loudspeakers behind the audience and was known as the effects channel.This channel increased the sense of space for the audience,but it also suffered from a serious technological limitation.Listeners seated on-center with respect to the rear loudspeakers perceived“inside-the-head”localization similar to the effect of stereo images reproduced over headphones.Listeners seated off-center localized the channel to the effects loudspeaker that was closest to them as dictated by the law of thefirst-arriving wavefront,thus destroying the sense of envelopment de-sired[14][Fig.2(a)].The solution to these problems was found by introducing a second channel reproduced over an array of loudspeakers along the sides of the theater to create a more diffuse soundfield[Fig.2(b)].In the mid-1970’s,a new sound technology was in-troduced by Dolby Laboratories called Dolby Stereo.It was based on the optical technology that had been used for sound onfilm since the1930’s,and it circumvented the problems associated with magnetic multitrack record-ing.Dolby developed a matrix method for encoding four channels(left,center,right,and mono surround)into two channels using a technique derived from the matrixmethods(a)(b)Fig.2.(a)In early surround-sound systems with a mono surround channel,listeners seated off-center perceived the sound as if it originated from the effects loudspeaker that was closest to them,thus destroying the desired sense of envelopment.(b)Current sys-tems use stereo surrounds reproduced over an array of loudspeakers along the sides of the theater to create a more diffuse soundfield.Fig.3.Current commercial multichannel systems encode the LFE,three front,and two surround channels into a bit stream thatis decoded at the user’s end.With proper loudspeaker selectionand placement,it is possible to simulate the experience of a movie theater.Dipole surround loudspeakers that do not radiate sound directly in the direction of the listener’s ears produce the best envelopment.used in quadraphonic systems but also ensured mono and stereo backward compatibility.In1992,further enhance-ments by Dolby were introduced through a new format called Dolby Stereo Digital(SR•D).This format eliminated matrix-based encoding and decoding and providedfive discrete channels(left,center,right,and independent left and right surround)in a configuration known as stereo sur-round.A sixth,low-frequency-enhancement(LFE)channel was introduced to add more head room and prevent the main speakers from overloading at low frequencies.The bandwidth of the LFE channel is limited between0and120 Hz,a frequency regime that is outside the localization range for human listeners in a reverberant room,thus simplifying the placement requirements for the subwoofer used for LFE reproduction(Fig.3).Recent advances in digital audio compression and optical storage have made it possible to deliver up to six discrete audio channels in a consumer format centered aroundKYRIAKAKIS:LIMITATIONS OF IMMERSIVE AUDIO SYSTEMS943the Dolby AC-3compression scheme.1With exciting new formats such as an audio-only digital video disc just around the corner,the number of channels could easily increase to ten or more.While there are several million consumer systems capable of reproducing more than two channels, the majority of users(particularly those with desktop com-puter systems)wouldfind the use of multiple loudspeakers impractical.In the sections that follow,we examine the requirements of systems that allow delivery of multiple channels over two loudspeakers using DSP to simulate certain characteristics of human listening.IV.S PATIAL(3-D)A UDIOA.Physiological Signal ProcessingThe human hearing process is based on the analysis of input signals to the two ears for differences in intensity, time of arrival,and directionalfiltering by the outer ear. Several theories were proposed as early as1882[15]that identified two basic mechanisms as being responsible for source localization:1)interaural time differences(ITD’s) and2)interaural level differences(ILD’s).A later theory by Lord Rayleigh[16]was based on a combination of ITD and ILD cues that operated in different wavelength regimes. For short wavelengths(corresponding to frequencies in the range of about4–20kHz),the listener’s head casts an acoustical shadow giving rise to a lower sound level at the ear farthest from the sound source(ILD)[Fig.4(b)].At long wavelengths(corresponding to frequencies in the range of about20Hz–1kHz),the head is very small compared to the wavelength,and localization is based on perceived differences in the time of arrival of sound at the two ears (ITD)[Fig.4(a)].The two mechanisms of interaural time and level differences formed the basis of what became known as the duplex theory of sound localization.In the frequency range between approximately1and4kHz,both of these mechanisms are active,which results in several conflicting cues that tend to cause localization errors. While time or intensity differences provide source di-rection information in the horizontal(azimuthal)plane, in the median plane,time differences are constant and localization is based on spectralfiltering.The reflection and diffraction of sound waves from the head,torso,shoulders, and pinnae,combined with resonances caused by the ear canal,form the physical basis for the HRTF.The outer ear can be modeled(in the static case)as a linear time-invariant system that is fully characterized by the HRTF in the frequency domain.As Blauert[17]describes it,the role of the outer ear is to superimpose angle-and distance-specific linear distortions on the incident sound signal.Spatial information is thus encoded onto the signals received by the eardrums through a combination of direction-dependent and direction-independentfilters[18],[19].The magnitude and phase of these head-related transfer functions vary significantly for each sound direction but also from person to person.1See Dolby Laboratories at.(a)(b)Fig.4.(a)In the low-frequency regime,sound is localized basedon differences in the time of arrival at each ear.(b)At higher frequencies,the wavelength of sound is short relative to the sizeof the head,and localization is based on perceived level differences caused by head shadowing.In the intermediate-frequency region,both mechanisms are active,and this can give rise to conflicting cues.The emergingfield of3-D audio is based on digital implementations of such HRTF’s.In principle,it is possi-ble to achieve excellent reproduction of three-dimensional soundfields using such methods;however,it has been demonstrated that this requires precise measurement of each listener’s individual HRTF’s[20].This seemingly funda-mental requirement that derives from inherent physiological and cognitive characteristics of the human ear–brain inter-face has rendered such systems impractical for widespread use.Current research in this area is focused on achiev-ing good localization performance while using synthetic (nonindividualized)HRTF’s derived through averaging or modeling or based on the HRTF’s of subjects that have been determined to be“good localizers”[21],[22].In his review of the challenges in3-D audio implementations, Begault[23]points out that there are currently three major barriers to successful implementation of such systems:1) psychoacoustic errors such as front–back reversals typical in headphone-based systems,2)large amounts of data required to represent measured HRTF’s accurately,and3) frequency-and phase-response errors that arise from mis-matches between nonindividualized and measured HRTF’s. It should be noted that front–back reversals can be reduced if the listener is allowed to move his head and that the lack of externalization experienced with headphone listening can be alleviated with appropriate use of reverberation.A fourth challenge arises from technological limitations of current computing systems.One capability that we envision for immersive audio systems is the simulation of room acoustics and listener characteristics for interactive, virtual-,and augmented-reality applications.In addition to the computational requirements for photorealistic rendering of visual images,the synthesis of such acoustical environ-ments requires computation of the binaural room response and subsequent convolution with the HRTF’s of the listener in real time as the listener moves around the room.Typical impulse response duration is3s,which,when sampled at48kHz,requires a processor capable of operating at944PROCEEDINGS OF THE IEEE,VOL.86,NO.5,MAY1998more than13Gflops/channel[24].This problem can be circumvented using special-purpose hardware or hybrid block fast Fourier transform/direct convolution methods [25].2The main goal is to reduce the number of operations for such computations,thus making them suitable for real-time interactive applications.B.Spatial Audio RenderingA critical issue in the implementation of immersive audio is the reproduction of3-D soundfields that pre-serve the desired spatial location,frequency response,and dynamic range.There are two general methods for3-D audio rendering that can be categorized as“head related”based on headphone reproduction and“nonhead related”based on loudspeaker reproduction[19].A hybrid category, called transaural stereo,also exists that allows loudspeaker rendering of head-related signals.It should be noted that there are other methods for three-dimensional sound-field capture and synthesis such as ambisonics[26]and wave-field synthesis[27],[28],but these will not be examined in this paper.Nonheadroom-related methods typically use multiple loudspeakers to reproduce multiple matrixed or discrete channels.Such systems can convey precisely localized sound images that are primarily confined to the horizontal plane and diffuse(ambient)sound to the sides of and behind the listener.In addition to the left and right loudspeakers,they make use of a center loudspeaker that helps create a solidly anchored center-stage sound image,as well as two loudspeakers for the ambient surround sound field.The most prevalent systems currently available to consumers are based on the formats developed by Dolby forfilm sound,including Pro Logic(four-channel matrixed encoded on two channels)and Dolby Digital(5.1-channel discrete based on the AC-3compression scheme).1Other 5.1-channel schemes include DTS Digital Surround3and MPEG-2.Multichannel systems were designed primarily for authentic reproduction of sound associated with movies but have recently started to be used for music recordings and games on CD-ROM.The5.1-channel Dolby Digital system was adopted in the U.S.standard of the upcoming advanced(high-definition)television system[29].The design requirements for such loudspeaker-based systems include uniform audience coverage,accurate localization relative to visual images on the screen,diffuse rendering of ambient sounds,and capability for reproduction of the wide (up to105dB)dynamic range present infilm soundtracks. Head-related binaural recording,or dummy-head stereophony,methods attempt to accurately reproduce at each eardrum of the listener the sound pressure generated by a set of sources and their interactions with the acoustic environment[30].Such recordings can be made with specially designed probe microphones that are inserted in the listener’s ear canal or by using a dummy-head microphone system that is based on average human 2See Lake DSP at .3See /.characteristics.Sound recorded using binaural methods is then reproduced through headphones that deliver the desired sound to each ear.It was concluded from early experiments that in order to achieve the desired degree of realism using binaural methods,the required frequency-response accuracy of the transfer functionwas,,andspeakerspeaker(speaker)the sound pressure delivered by each loudspeaker.To accurately reproduce the desired binaural signal at each ear,the inputsignalsFig.5.Transfer functions associated with a loudspeaker sound-rendering system.To deliver the correct binaural sound, it is necessary to prefilter the signal to the loudspeakers so that thecross-talk terms H LR and H RL are cancelled during reproduction.ear speakerear speakerear earear earFig.6.The time-domain response of a loudspeaker system includes the direct sound as well as the sound due to multiple reflections from the local acoustical environment.Psychoacoustic evidence indicates that in order for these reflections not to be perceived,their spectrum level should be 15dB below the level of the directsound.Fig.7.Frequency-response problems that arise in the low frequencies due to standing-wave buildup in small rooms and in higher frequencies due to interactions with elements in the local acoustical environment (e.g.,CRT screen,table top,untreated walls).midbass frequencies.Furthermore,even if it were possible to place the loudspeakers far away from large reflecting surfaces,this would only solve the problem for middle and high frequencies.Low-frequency room modes do not depend on surfaces in the local acoustical environment but rather on the physical size of the room.These modes produce standing waves that give rise to large variations in frequency response (Fig.7).Such amplitude and phase distortions can completely destroy carefully designed 3-D audio reproduction that relies on the transaural techniques described above.B.Design RequirementsTo circumvent these limitations,a set of solutions has been developed for single-listener desktop reproduction that delivers sound quality equivalent to a calibrated dubbing stage [43].These solutions include direct-path dominant design and correct low-frequency response.Based on our current understanding of psychoacoustic principles,it is possible to combine such cues to place the listener in a direct sound field that is dominant over the reflected and reverberant sound.The design considerationsKYRIAKAKIS:LIMITATIONS OF IMMERSIVE AUDIO SYSTEMS947Fig.8.A properly designed direct-path dominant system that compensates for frequency anomaliesproduces a muchflatter frequency response.Frequencies below100Hz are reproduced with aseparate subwoofer(response not shown)that is placed at a known distance from the listener toalleviate anomalies from standing waves.for this direct-path dominant design include compensationof the physical(reflection and diffraction)effects of thevideo/computer monitor that extends the loudspeaker baffleas well as the large reflecting surface on which the computerkeyboard typically rests.The distortions that arise from am-plitude and phase anomalies are eliminated,and this resultsin a listening experience that is dramatically different thanwhat is achievable through traditional near-field monitoringmethods(Fig.8).Standing waves associated with the acoustics of smallrooms give rise to fundamental limitations in the qualityof reproduced sound,particularly in the uniformity of low-frequency response.Variations in this frequency regime canbe as large ass apart),thereby giving rise to acoustic crosstalk[Fig.1(b)].These time differences,combined withreflection and diffraction effects caused by the head,lead tofrequency-response anomalies that are perceived as a lackof clarity[48].This problem can be solved by adding a cross-talkcancellationfilter(as described above in the descriptionof transaural methods)to the signal of each loudspeaker.While this solution may be satisfactory for the static case,as soon as the listener moves even slightly,the conditions948PROCEEDINGS OF THE IEEE,VOL.86,NO.5,MAY1998Fig.9.Desktop sound system with vision-based head tracking.In this early prototype,the time difference of arrival at the two ears is adjusted in real time as the listener moves in the plane parallel to the loudspeakers.Current research is focused on tracking,pose estimation (for head rotations),and pinna shape recognition for real-time cross-talk cancellation and individualized HRTF synthesis.for cancellation are no longer met,and the phantom im-age moves toward the closest loudspeaker because of the precedence effect.In order,therefore,to achieve the highest possible quality of sound for a nonstationary listener and preserve the spatial information in the original material,it is necessary to know the precise location of the listener relative to the loudspeakers [47],[49],[50].In the section below,we describe an experimental system that incorpo-rates a novel listener-tracking method in order to overcome the difficulties associated with two-ear listening as well as the technological limitations imposed by loudspeaker-based desktop audio systems.VI.F UTURE R ESEARCH D IRECTIONSA.Vision-Based Methods for Listener TrackingComputer vision has historically been considered problematic,particularly for tasks that require object recognition.Up to now,the complexity of vision-based approaches has prevented their being incorporated into desktop-based integrated media systems.Recently,however,von der Malsburg’s Laboratory of Computational and Biological Vision at the University of Southern California (USC)has developed a vision architecture that is capable of recognizing the identity,spatial position (pose),facial expression,gesture identification,and movement of a human subject in real time .This highly versatile architecture integrates a broad va-riety of visual cues in order to identify the location of a person’s head within the image.Object recognition is achieved through pattern-based analysis that identifies con-vex regions with skin color that are usually associated with the human face and through a stereo algorithm that determines the disparities among pixels that have been moving [51].This pattern-recognition approach is based on the elastic graph matching method that places graph nodes at appropriate fiducial points of the pattern [52].A set of features is extracted at each graph node corresponding to the amplitudes of complex Gabor wavelets.The key advantage of this method is that a new pattern (face or ear)can be recognized on the basis of a small number of example images (10–100).For audio applications,in whichthe system must remember the last position of a listener that may have stopped moving,a hysteresis mechanism is used to estimate the current position and velocity of the head with a linear predictive filter.While there are several alternative methods for track-ing humans (e.g.,magnetic,ultrasound,infrared,laser),they typically are based on tethered operations or require artificial fiducial markings (e.g.,colored dots,earrings)to be worn by the user.Furthermore,these methods do not offer any additional functionality to match what can be achieved with vision-based methods (e.g.,face and expression recognition,ear classification).B.Desktop Audio System with Head TrackingA novel multichannel desktop audio system that meets all the design requirements and acoustical considerations described above has been developed by Holman of TMH Corporation 4in collaboration with the Immersive Audio Laboratory at USC’s Integrated Media Systems Center (IMSC).5This system uses two loudspeakers that are po-sitioned on the sides of a video monitor at a distance of 45cm from each other and 50cm from the listener’s ears (Fig.9).The seating position height is adjusted so that the listener’s ears are at the tweeter level of the loudspeakers (117cm from the floor),thus eliminating any colorations in the sound due to off-axis lobing.We have also incorporated the vision-based tracking algorithm described above using a standard video camera connected to an SGI Indy workstation.This tracking system provides us with the coordinates of the center of the listener’s head relative to the loudspeakers and is currently capable of operating at 10frames/s with a 3%accuracy.In this single-camera system,it is possible to track listener movement that is confined in a plane parallel to loudspeakers and at a fixed distance from them.When the listener is located at the exact center position (the sweet spot),sound from each loudspeaker arrives at the corresponding ear at the exact same time (i.e.,with zero ipsilateral time delay).At any other position of the listener4See .5See.KYRIAKAKIS:LIMITATIONS OF IMMERSIVE AUDIO SYSTEMS949。
