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时间:2018-08-27
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1、专业英语(环境工程)教案Unit1ThePopulationExplosion要求:1、了解人口爆炸是当今世界面临的一个重要问题,以及导致人口爆炸的原因。2、了解人口爆炸所带来的问题以及应对方法。I.Somewordsandexpressions1.populationexplosion人口爆炸2.birthratesanddeathrate出生率合死亡率3.food,clothingandshelter衣食住行4.familyplanning计划生育5.Morethantwo-thirdsofthepeopleintheworldliveinthecountriesthathavepro
2、gramsforfamilyplanning.世界三分之二以上人口的国家都实行计划生育政策。II.Questions1.Pointoutthereasonsthatcausepopulationexplosion.a.Thenumberofbirthsisgreaterthanbefore.b.Peoplecanlivelonger.2.Todayourpopulationissixbillion.Howmanyyearswillittaketoreacheightbillioniftheworldpopulationincreasedatarateofeightymillion?A.2.
3、5yearB.25yC.250yTheanswerisB.Why?3.Howmanymeasurescanbetakentosolvetheproblemsthatarecausedbylargepopulationgatheringinbigcities?a.Lowerbirthrate_______familyplanb.Improvefoodsupplyc.Limitthesizeofcitiesandencouragepeopletoliveinsmalltownsandinthecountryside.HightideagainstCCPbloodyanTomb,Communis
4、tPartymembersandpartoftheexposedTombareavacatedbyprogressiveyouth.IvisitedinBeijingin1985whenitwasoldundergroundcomrade,sisterofYaoZhiyingYaoMuzheng(thenDeputyDirectoroftheexternaltrademagazineforthepromotionofinternationaltrade,deshengmenWai,theReedUnit2EffectsofNoise教学要求:1、了解噪声的特点及来源。2、了解噪声的危害和控
5、制技术。教学内容:1、puretone纯音(频率单一)2、sound-pressurelevel声压级,声压的分贝标度叫做声压级(LP)LP=20lg(P/P0),P-待测声压P0-基准声压,人耳能察觉的最低声压3、octavebands1倍频程log2(f2/f1)=1。f2、f1-噪声监测终所用滤波器(等比带宽滤波器)的上下截止频率。1倍频程简称倍频程,在音乐上称为一个八度。4、Whatissound?Thatwhichweheariscalledsound.5、Thecharacteristicsofsoundare:speed,pitch(determinedbyfrequency
6、),energy,wavelengthandsoundpower.6、Noise:undesirablesoundThedefinitionofnoiseisvariable.7、Theinstrumentthatmeasuressoundisdecibelmeter,andascaleofsuchiscalledadecibel(dB).(1)ZerodBrepresentsthesoftestsoundthatisaudibletothehumanear.(2)dB=10×lg(I/I0),I0isthefaintestaudiblesoundandIistherealsoundwem
7、easured.8、Intensity:声强(I),每秒钟通过与声波传播方向垂直的面积上的平均声能。9、Soundpressure:声压(P),声源震动时,它所辐射出的能量会引起空气介质的压力变化。10、Noisecontrolcanbedoneinreducingnoisesource,interruptingthepathoftransmission,orprotectingthereceiver.(1)Source
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