2004——2005第一学期期末试卷答案
20042005高三上英语期末考试卷及答案.doc
福建省厦门第一中学2004—2005学年第一学期期末考试高三年英语试卷第一卷（三部分，共115分）第一部分：听力(共两节，满分30分)第一节(共5小题；每小题1.5分，满分7.5分)听下面5段对话。
每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项，并标在试卷的相应位置。
听完每段对话后，你都有l0秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
1. What do we know about the man?A. He is overweight.B. He won’t give up smoking.C. He is suffering a heart attack.2. What is the man going to buy?A. Food.B. Drinks.C. Flowers.3. What are the two speakers doing?A. Looking for some suitcases.B. Booking tickets for a journey.C. Checking the woman’s baggage.4. Why would the woman rather stay at the hotel?A. It costs less money.B. It saves much labor.C. It feels more comfortable.5. What are the two speakers talking about?A. A painting.B. A country scene.C. A kind of drink. 第二节(共15小题；每小题1.5分，满分22.5分)听下面5段对话。
每段对话后有几个小题，从题中所给的A、B、C三个选项中选出最佳选项，并标在试卷的相应位置。
听每段对话前，你将有时间阅读各个小题，每小题5秒钟；听完后，各小题将给出5秒钟的作答时间。
北京联合大学2004-2005学年第一学期《大学英语》期末考试卷及答案(A卷)
北京联合大学《大学基础英语》2004一2005学年第一学期期末考试试卷（A卷）班级姓名学号成绩Part I Listening Comprehension (20%)Section One Conversations (10%)Directions: In this section, you will hear 10 short conversations.At the end of each conversation, a question will be asked about what was said.Both the conversations and the questions will be spoken once.After each question there will be a pause. During the pause,you must read the four choices markedA,B, C and D , and decide which is the BEST answer.1.A.at a meeting B.in the office C.in the city D.out of the town2.A.30 minutes B.20 minutes c. 25 minmutes D.15 minutes3.A.go to work by bicyele B. take a taxi to workc.go to work on foot D.go to work by bus4.A.Physics is very difficult. B.He will probably take physics.c.He will not take physics. D.Physics is his favorite subject.5.A. to see her friends in New York B. to have a tourc. to visit her parents in New York D.to New York with her parents6.A. music B.readimg a book C. a long qucuc D. waiting7.A.a clcrk B. a waiter C. a postman D. a salesman8.A.They shouldn't go to the theatre. B. The subway is slower than a car.C.The subway is faster than a car.D.They can go to the theatre without a car.9.A.He agreed that it was a good meeting. B.He thought it was not a good proposal.C.Her support would have helped him this morning.D.Her support would count for nothing.10.A.If she will do the job. B. What the woman is goimg to do.C.How the woman's health is.D.If the weather is goodSection TwoPassages (10%)Directions: In this section, you will hear 3 passages.At the end of each passage, you will hear some questions.Both the passages and the questions will be spoken only once.After you hear a question, you mnst choose the best answer from the four choices marked A,B, C and D.Questions ll to 13 are based on the passage you have just heard.11.A. its rivers B. the sea C. the gold and silver D. its mountains12.A. to spend a holiday B. to ski on mountainsC. to look for gold and silverD.to travel in Colorado13.A.People living in the cities and towns most like to dig gold in the moumntains.B. Many of them serve in the army and air force and govemment agencies.c. Only a few work in the industries.D.Many of them work in agriculture.Questions 14 to 17are based on the passage you have just heard.14.A.the care and proper selection of dogs for family petsB. different kinds of dogzsc.different kinds of books about dogsD.the responsibility of the parents15.A. from a pet store B.from friendsC. from the books about rarious kinds of dogsD. from the owner of the dogs16.A.Because they are easy to train. B. Because they are aggressive.c.Because thay are big. D.Because they proride companionship as well as protection17.A.when your children are young B. when you live in the city.c. when the space is limited. D.when you live with your parents. Questions 18 to 20 are based on the passage you harve just heard.18.A.. because there are msny developimg nstions.B. becanse people use too msny man-made materials.c.becatuse we have more snd more industries.D.because we are building more comfortable houses.19.A. industry B.health C. the funure of our children D. elean air20.A.No one knows where the society is going-B.People don 't welcome the rapid development of moden society.c.The speaker is womied about the fuure of our modem society.D.Man can do nothing about the problem of pollution.Part l Readling Conprehension (30%)Passage OneSuicide is on the rise in parts of AsiaoA person thinking sbeut taking lhis own life ofen exhibits waning signs, such ss depression,anxiety,hostility oranger.Learming to recogmize these zigns may save someone s life.Most sucides are the conseqtuence of depression.Tesve sigas distinguish resal depressicn fiom oceasional unhsppiness: 1.xviewing thingsonly in the mot negzative terus. The depresed peson its convinced that life will never get beter.2.Avoiding friends and social activities.Safden withdrawal is a signal of distes. 3.Chsnging daily potrenmis dramstieally.when a good sleper suddenly becomes an insomnisc,alighn eater develops a gpreedy appetie, a quiet person funs extrernusely sactive, and there s a chsnce he 's sufEering from depression.Not all depressei pecple are suicidal.Many older adults know that perils (危险) of sadness will pass.They aze more likely to seekprofessionsl heip. Youme people and younger adits often think depresiion will neyer endExperts tel us some suicidal people proride clear-cut sigals of their plan. For instance, some youths send notes or cas.ette tapes toreveal their feelings of depression or helplessness. So leam the signs and do something: life is too important to risk,1.The writer believes thatA. even occasional unhappiness will inevitably lead to suicideB.an emotional person will most likely commit suicideC.all depressed people are suicids1D.suicide can be prevented if ceitain signs are recognized2.According to the passAge, a peTson attempting suicide often shows the following signs EXCEPT thatA. he belieses that life will never get betterB. a previously quiet peason suddenly becomes unasually activeC. be is seeking professional helpD. be suddenly stays away from social activities3.The word "insomniasc” (Para.2,Line 3 ' most probably meansA.a sleepless personB. an unhappy personc. a talkative person D.a senisitive person4. It can be inferred from the passage thatA. suicide is on the decline in other parts of the worldB.before trying to commit suicide, one usually shows some signsc. a person without friends is sure to commit snicideD.older adults never attempt suicide5. Which of tihe following may be the title for the passage?A.An Inevitable Pesult of DepressionB.Suicide Can Be PreventedC.Suicide Is On the RiseD. Danger of Changing Daily Pattems Passge IwoBathing in the soea in England a hundred years ago was not quite the lght-bearted amusement fthat it is today. There was DO runing down ftom the hotel to the beach in a batb robe,加subathing or lying about 咖the sands in bathigdes ater the dip (侵泡).Everything had to be done in an orderly and extemely polite mamer Mixed bathing wass not alowed anywhere. Men and women each had their separate part of the beach and they were nDot supposed to meet im the water.Bathing clothes were also closely cotolled Men usally wore simpl bathing dawers and no more, but women were obliged (被迫)to wear thick, cumbersome woolen guments that corvered them completely fom head to foot., These satisfhed the demands of modesty, but fthey rmust have been extenely umcomfotable for swinming.Even thus decently covered, women were not supposed to show themselves om the beachwhile in bathing costume. They had to wait tbeir tum for a bathing machine. a sot of woodkan cabin om whels which was drawn night down to the water's edge by horses. On its seaward side a sort of hood or camopy (伞盖) stetched outwards and dowwads over he water, completely hiding the batber wtal she was actually in the sea. There was a bathing woman in atendance, part of whose duty was to dip. in otber words, to seize the batbher as soon as she emerged and dip ber frcibly under water two or three times. This was supposed to be for the benefit of her health and no doubt it wasall right in the hands of the gentle. But mosot bathing women mere reverse of the geale. and to be diped by them must have bee a steuouss (艰苦的) fom ofexercise.6. Modem bathersA wear thick, ucomfortable bathing clotbesB. use hose-drawm bathing machinesC. aen't alowed to sumbatheD. have mixed bathing om the beach and im the sea7. Women wore uonortble bating clothes becauseA it porected from coldB. it Was considered bad moanners to show auy fleshC. itmade it easier to smwimnD. it was requird by the rgulations8. Why was the bathing muachines used?"A So that the horses could drimnk at the water's gate.B. So that the hood could be projected towards the seaC, So that the bather could hide from tbe seaD. So that tbe bather could be screened umtil she was in the a9. A bathing -woman's job was toA. ated to the bathing machineB. dip the atendaceC. force the bather to emerge ftom the bathing machineD. force the bather under the water when sbe came out of the machine10. A sitblet title for this pasage would beA. Sea Bating through the AgsB. Bathimg cothes through the AgesC. Sea HorsesD. Hundred Years of Sum BathingPassage ThreeThe loudest outery(强烈反对)about povety (贫困) seemed to come in the wealhiest coumty -by for in the world. According to most calculations, tbough most of tbe 19541970 period the United States had a standard of living well above Europe's and may times above the world average. Y'et protests about erinding porverty, humger and dreadful need poceed (继续下去》more fom the United States than from counties with cn-6fcieth of ther living (An anmual per capita income of eight dllas 1s typcal of mch of Africa and Asia and not a ltle of South America). It would衣em suange t如these psople ( were they only avare of the fxct?)y that Amernican ndicals demand a retreat froman American commitment 0o the fr comers of tbe globe 50 that tbe mobey thus saved can be spent raising the standard of living of udepriliged (下层的) Amercans.What this last print suggests is not s0 mnch that hummn wnts are mever to be stastfied though this is doubtles toue. and the Americn suburbanite (郊区居民) deprived ofhis second car ad his color ” suffers just a acutely韶a African farmer in peed of a second cow and a screen door. Rather, it suggests the esteat of contempoary break of social nonns - the emaeiation of the individual self. People have leamed that their wants are scare and their right ought to be satisfed. They have leamed to consider any obstacle to personal fullment a intolenble insult. They have greatly expanded the circle of self awaen族They加longer accet shap laninations份日) op individual desires im the nane of the group. The amoumnt of potential buman discontet has always been infnite - misery, failure, msfting bitress,hatred, enry beyond eling It bhas usally failed of uterace (讲言表达) , and in the past it vwas accepted pasvely as being beyond belp.11. According to the passage most complaints over a poor living standard were made by those who came from___A. the United StatesB. Asian coumtriesC. the European CommityD. Commonwealth ofNations12 The average income for each Ameican a year during the 60s was most ikely in the bigborod of .___A. 1120 dllarsB. 40 dllarsC.320 dllrsD. 80 dllrs13. n onder to inprove the staodand of living of poor Amenicas, dhe exuemits in the Stotes demand.___A. a fll tax elief on cizeas lving oveveasB. a stop to arms race gainst ations far awyC. a cw im financial stace 0 poor coutiesD. a farorable blaoce of tade nih foreiepe coumties14. The real cause for dhe most fctuste people to potest about porety lies in.A.enhsocod consciousnes of selfB. their ece sthtusC. limiations of bumam maueD. contlict in lass itees15. Fom the last sentracte, in e国bwe safely infered that outry about poverty in effect involves people'sA ahilty to sufer a hadife B. unestanding of their rightsC. polial atiude tmurd the govermeatD. mbole outlook o fferent EfestylesPart III Vocabulary and Structure(20%)1. The city is planning a public to awaken people to the problem of the environment pollution.A. CampaignB. missionC. paintingD. rescue .2. The Party calls on us to___ the West and a lot of uiversity students go there ater graduation.A. ExpandB. explodeC. exploitD. execute3. "Here you are at last" ongrily bis mother.A. ClaimedB. exclaimedC. liedD. leaned4. His first year at Oxford bore__ fruir be pubihied ro bo sad ten papers.A. CriticalB. abundantC. militaryD. relative5. The weather sieututs a series of cold days in te future.A. Reflected B restricted C. nepleced D. prdctedd6. ltis nceary dhat pacpl.and: ipove these olfashioned aircnais.A. MolilyB. elaily C bonity D. satindy .7. Thoghbhe is imerir to sowe stuft in fc,be is the____ m muge of the busimessA. TopicalB. speficialC. ritalD. rtual8. There is ofena___ loss of sigh is old ageA. TrvingB. competive C popressive D. executivee9. The back paint o fbe dor porides a___ for tbe whit wll.A. Conest B contast C. comsct D. conat10. The dortor._the: ptie to be operzed xt cace.A. CousetedB. brkedC. aiciedD. unloled11. Ow itucto_ that we should not te anyone about tis.A. QualtyB. decay . c pecty D. bother12. Hearing a cry for belp. the youmg mom nushed to the bamk and.into the rives to save the cowning bory.A. BestedB. plomgedC. devoledD. rteated13. Yom ither's rcewmsr_ it wam treal recovery and please keep am ep唱him further.A. AmkwrdB. supeficinlC. psblD. imfnite14, Though dtey sid woting aboat it Ihom they wushawew__ int de conse ofitA petated B. reulated C. fusuated D. Desxnbed15. Since be is my boss, he paid mea.five huwdued pounds a mouth.A steady B. prior C. novel D. louely16_.__ by their quality I decided to place a big order for tbe productA Having impressed B. Being impressed C. Impressed D. Impressing17. To our supise the bride's mother didn't.at the wedding ceremoay.A. rm intoB. fl uponC. showD. cut of18.the efot and good will of everyone inroled the Christnas party Wwas a great sucess.A As oif B. Thanks to C. Upto D. Delighted with19. The auhor is of the opinion that early success may prove bamful to a person'salroundd development,A in the long nmn B. for the time being C. all day lomg D. side by side20. The city govenment's frst____ is to buildl a Bew ainport lhis yearA Loan B. sting C. depatpent D. piority21. Jobm said that he owed it.his teacher that he wom the first price in the English spech contest.A from B.of . C. to D.at22. Qalifed dploas(外交的sbouldbe able to___ whatever statoms they find teselres imA show up B. mm into : C. imbue with D. cope with23. If James hadn'tbeen there to_ the awlkward moments, the meeting would have beena disaster.A snoo over . B. limk u C. branch out D. pickp24. I'm somry, but I relly can't so out with you tomighet; I have to.my homework.A .nm outof B. catchup om C. make room for D. smeak of to23. The problem our atindes towurd thnking not in nidiculous govemmen regulations.A lies in B. believes in Cin D. speialies in26. Tim always keeps a certaim anoumt of moaey.m case of an energency.m.B. im useC. on handD. on business27.was a very besutful birthday present that Mary got fom ber auntA. ThisB. That D.It28. Bobby is a small staff in this company, but he tlks to everyone inp the ofie asifhe_ the boss.A. IsB. wereC. hadbeenD. has been29. This place馆as rportedto.an eathquake reistered 7.5 o如tbe Richer scale yesterday.A have bad B. have C. have been had D. be having30. The youmg man adnmited _errors in judgment om more than one occasion.A tomake B. making C. to have made D. made31. A womanwho__ the acident said that both cars were going at high speed wben they crasbedA riolated B. obeyed C. witbessed D. screaned32. People did not see the bomb dropping but they could bear the. several miles away.A extension B. esplosion C. secunity D. spectators .33. The company began by specalizing im nadios but has now decided to nto computers.A branch out B. tum dovn C. take stock D. coumut on34. Ata very ealy age sbeA. PreupedB. sbieldedC. dsigisbedD. moirated35. le wese told tbat tbe foall game had been___ mtil the floming Fidary becouse of the bad wenber.A, signed B. sought C. quified D. posponed36. Jim etetrd de Speech Comtes wileous wch hope, not tinking that he would.. witb the fnst paizeA. EaduφB. est out .C. put downD.ip中.37. Saoking i,,tor mamy ditses swch程lung eamcer, hean amack and high blood peswe,A. Pgessire B teortical C. respousible D. amkwurd38. A the disasston the epeleiee Camre中w谐oy good ides xbout the Dew电uB____A. RlativityB. regulationsC. speisD. taleas39. No mter bow for awy Bb was. bis parents wee. tatbe would come brck o see tbem an the Sping Ftiral.A recmmendeddB selected C. iled D. cominced40. The anpocr's sytes Ta n tfcient a m got om aplame wih a boub without being dcoredA desoasmnionB pese C. eplosion D. secuityPartIV Cloze (10%)Dietioas: Please山im tbe blanks wih the erat words from the testBalscing wons md school was dicu "1 ws sarying中late shudying. and going to wok early ervery moming I was haring a haxrdcocetating i els, and a hud ia u the job beaure I was 10 imod." she say But she ended__2_ wid twe A's in her finst semeser amyway.Picilla decided_ 3_ purue m acbaeloeyr majcr and in the smmme of 1991, she got ber finst oportaity t如Teally best_ 4_ herioe in he aubjet The achelogian Botld chool of Wwashington Stue Uunrersty wws sponoring a smr retrch pojtet糕消it_3_ the Souke Rire im Wetingpon Pisxila erer herel_ 6_ he wonk, and pojer sperisors mre ipesed_ 7_ dbe eadof the smmmer oflhe prefeson efered ber a jo. "He ad "We pw wa coumnet tor a poper in Nerth Dakom We wanto_ 8_you it you're wlling to tike a semetser of fom so"he 9_ was a drepion fou Pici's pursait of ber BA.“But by the Ioo longer doubted fatTrould utiantl fmish shoo 10_ I felt coforabl gabbing this oposis; she saysPart V Translatio (20%)Secian A Put tbe flomig retroces into Chinese (10%)She plomnged into the paints naod before I lhew it she bad mept sevenal ferce stroibes ad slushes of bhue on the absoutely emifed cavas In Confucian plosop the family plays 1 cecbal tole -蹈oicanteso that leads people t1o worlk for the hopor of的e faul nt just ftor temebre.,Ibey felt confortble asing bis adrice on a mide amge of atte icluding the odbeharior of teir piters across山e ocam4. Succes, which eancounges rpreition of eld bwehurioc. 船non smeatly a good a 1eacber as tilue Known 10 mls趣and wide. for hts boo d BrielHiusony ef Time. Stepben Hmking ts a st物clem博tm more ways to aee Setim B Put the floig sealeaces ine Engih a09) i. 他在尝试制定促进恩考艺术的新计划时脑子里闪过了一个绝妙的主意。
2004～2005 学年第一学期《高等数学》期末考试试题A卷与答案
n 22004～2005 学年第一学期《高等数学》期末考试试题 A 卷（216 学时） 专业班级学号 姓名一、填空题：（4×5 分）♣a (1 - cos x ) ♠ x > 0 ♠ x 21、设 f (x ) = ♦4 x = 0 连续，则常数 a = ， b =♠b sin x + ⎰ x e t d t ♠ 0 ♥♠ x x < 0∞∞2、设∑ a xn的收敛半径为 3, 则∑ n a (x -1)n +1的收敛半径 R ＝n n =1nn =13、已知 f (x ) = x (1 - x )(2 - x )…(2005 - x ) ，则 f '(0) ＝∞14、级数∑ nn =1的和 S =二、选择题：（4×4 分）1、函数 f (x ) = (x 2- x - 2) x 3- x 不可导点的个数是A 、 0B 、1C 、2D 、32、设周期函数 f (x ) 在(-∞,+∞) 内可导，其周期为4，且limf (1) - f (1 - x )= -1，x →02x则曲线 y = f (x ) 在点(5, f (5)) 处的切线的斜率为A 、 2B 、－2C 、1D 、－1∞n -11 k3、对于常数k > 0 ，级数∑(-1)tan n + n 2n =1A 、绝对收敛B 、条件收敛C 、发散D 、收敛性与 k 的取值相关4、设函数 f (x ) 有任意阶导数且 f '(x ) = f 2(x ) ,则 f(n )(x ) = (n > 2) .A 、n ! fn +1(x ) B 、nfn +1(x ) C 、f 2n(x ) D 、n ! f 2n(x )x ⎰ ♥三、计算下列各题：（6×6 分）arctan x - x1、求极限： lim3x →0ln(1 + 2x )2、设 y = tan2x + 2sin x，求： d y x =π23、设函数 y = y (x ) 由方程e y+ 6xy + x 2- 1 = 0 确定,求： y '(0)e x + e - xf '(x ) f (x )4、已知 f (x ) =,计算不定积分： 2+ f (x ) f '(x )d x5、设函数 y = y (x ) 由参数方程4 ln x♣♠x = t 3 + 9t ♦♠ y = t 2- 2t 确定，求曲线 y = y (x ) 的下凸区间。
04-05年上学期初一期末试卷英语(附答案)
2004—2005第一学期初一英语期末试卷一、词汇：(10分)A、根据释义，拼写单词。
（5分）1、costing a lot of money x, p, s, i, e, e, e, n, v2、a cut in price i, c, o, s, d, n, u, t3、as much as you want n, e, u, h, g, o4、it is sweet and brown e, o, c, l, h, c, t, o, a5、do sports activities r, i, s, e, e, c, x, e,B、根据句义及首字母提示，在空格处填入一个恰当的词。
（5分）6、We raise money to help the children in p areas.7、There are four seasons in a year. They are spring、summer、autumn and w .8、Would you like to have some n for breakfast?9、She s 100 yuan buying books every year.10、Are you f this afternoon? Let’s go to the park together.二、用所给词的适当形式填空。
（10分）1、The girl with a pair of (glass) is Sandy.2、(walk) is good for health.3、Millie is very polite and (help).4、Different (country) have different languages(语言).5、Look! The man (talk) with a woman.6、What she usually (eat) for lunch?7、There (not be) some milk or eggs in the fridge.8、Simon is good at (play) tennis.9、She likes (watch) TV very much.10、(not look) out of the classroom.三、根据要求改写句子。
郑州大学2004至2005第一学期化工原理期末考试试题及答案
郑州大学2００4至２005第一学期化工原理期末考试试题及答案Ａ卷一、选择题:（每题 2 分,共 2４分）1.利用因次分析法的目的在于Ａ。
A 减少实验工作量B 增加实验结果的可靠性C 建立数学表达式D 避免出现因次错误2．牛顿流体在管内作层流流动,流体层之间的剪应力在 B 。
A 管中心最大B 管壁处最大C 管中处处相等Ｄ管壁处最小3.流体通过离心泵所获得的能量主要表现为 B 。
Ａ动能增加 B 静压能增加 C 位能增加 D 流量增大4.用离心泵把地下贮槽中的液体送入高位槽，完好的离心泵却无法泵送液体，可能导致故障的原因是 C 。
A 贮槽内液面上升B 液体温度下降C 吸入管堵塞D 容器内压强升高5.回转真空过滤机的转速越快，单位时间所获得的滤液量就越___＿_,形成的滤饼层厚度就越__＿_＿，过滤阻力越__＿___。
ＣA 少,薄,小B 少，厚，大C 多，薄,小D 多,薄,大6.离心沉降速度是Ｂ。
A 颗粒运动的绝对速度B 径向速度C 切向速度D 气流速度7、气力输送过程中,垂直管中稀相输送时气速的下限为 B 。
A 颗粒的沉降速度B 噎噻速度C 起始流化速度Ｄ表观气速8．穿过三层平壁的稳定导热过程，已知各层温差为Δt１＝4０℃，Δt2＝35℃,Δt3＝5℃,则第一层的热阻R１与第二、三层热阻R2、R3的关系为Ｂ。
A R1>(R2＋Ｒ3)ＢR1＝(R2＋R3）C Ｒ1＜（R2＋Ｒ3)D 无法比较;9．在无相变的对流传热过程中，热阻主要集中在＿_____，减少热阻的有效措施是___＿__。
CA 层流底层,使流体处于层流状态Ｂ流体湍动区域，使层流底层减薄C 层流底层,提高流体湍动程度D 流体过渡区域，提高流体湍动程度10．在蒸汽冷凝传热中，不凝性气体的存在对对流传热系数α的影响是___A___。
A 不凝性气体的存在会使α值大大降低B 不凝性气体的存在会使α值升高C 不凝性气体的存在与否，对数据无影响D 不一定1１.把一壳程用饱和水蒸气加热管内水的列管式换热器由单管程改为双管程,会引起Ｂ。
北京邮电大学 2004-2005学 年第一学期通信原理试卷附答案
F 1 , K pa F 2 , K F , K pa北京邮电大学 2004-2005学 年第一学期期末试卷附答案一. 填空（每空 1 分，共 16 分）1. 调相信号 s (t ) = A c cos ϒ≤2π f c t + K P m (t )/ƒ，其解析信号（即复信号）的表达式为 ，其复包络的表示式为。
2. 循环平稳过程的定义是。
3. 用基带信号 m (t ) = 2 cos 4000π t 对载波c (t ) = 20 c os 2π f c t 进行调频，若调频的调制指 数是β f = 9 ，则调频信号的时域表达式s (t )=，其信号带宽B = Hz 。
4. 若多级线性网络的第一、二、……及第n 级的噪声系数及功率增益各为 1 、2、…、 n，则级联后的总噪声系数F 为 。
5. 一 MPAM 数字通信系统每隔 0.1ms 以独立等概方式在信道中传送 128 个可能电平之一，该系统的符号传输速率为 波特，相应的信息传输速率为bit/s 。
6. 数字 PAM 信号的平均功率谱密度取决于及。
7. 在 条件下，BPSK 和 QPSK 的平均误比特率相同，但后者的功率谱主瓣带宽是前者的一半。
SC = B l og 2 1+8. 仙农信道容量公式N 0 B 是在 条件下推导得到的。
c 1 29. 利用线性反馈移存器产生 m 序列的充要条件是。
m 序列应用于扩频通信，可利用 m 序列的 特性进行解扩。
10. 最小码距为d min = 7 的线性分组码可以保证纠正 个错，或可保证检测 个错。
二、选择填空（每空 1 分，共 14 分）从下面所列答案中选择出恰当的答案，将对应英文字母填入空格中，每空格只能选一个答案(a) 减小(b )增大(c )不影响 (d )AMI (e )Manchester(f )CMI (g )HDB3 (h )系统在载频附近的群时延(i )时延(j )在信息序列中引入剩余度 (k )对有剩余度的消息进行减小剩余(l )可靠性 (m )有效性 (n )编码信道 (o )恒参 (p )调制信道 (q )随参 (r )等于 8bit (s )等于 4bit(t )小于 4bit (u )大于 4bit1. AM 信号通过带通系统，当带通系统在信号带宽内的幅频特性是常数，相频特性是近似线性时，通过带通系统后信号包络的 等于 。
宁国市2004~2005学年第一学期期末
宁国市2004~2005学年第一学期期末初二数学试题考试时间：100分钟满分：100分一、填空题(每题2分，共16分)1、关于一点成中心对称的两个图形，对应线段_________。
2、已知正方形的一条对角线长为4cm，则它的面积是_________cm2。
3、已知□ABCD中，∠A比∠B小20O，那么∠C的度数是______。
4、恩格尔系数表示日常饮食开支与家庭经济总经济收入的比例，它反映了居民家庭的实际生活水平。
各种类型家庭的的恩格尔系数如表中所示，则用含n的不等式表示小康家庭的恩格尔系数为-的值不小于1。
5、当x___________时，代数式46、若2n=3,3n=6，则6n=_________。
7、若x、y 是正整数，且2x·2y=32，则x+y=__________。
8、当抛掷两枚重量均匀的骰子时，出现“一正一反”这个事件的机会是__________。
二、选择题(每题3分，共24分)1、下列图形是我国几家银行的标志，其中既是中心对称图形，又是轴对称图形的个数为( )A、1B、2C、3D、42、在□ABCD中，EF∥AD，MN∥AB，EF、MN相交于点P，则除□ABCD外，图中还有平行四边形的个数为( )A、4B、8C、8D、103、矩形具有而一般平行四边形不具有的性质是( )A、对角相等B、对边相等C、对角线相等D、对角线互相平分4、如图，天平右盘中每个砝码的重量都是1g ，则图中显示出某药品A 重量的范围是( )A 、大于2gB 、小于3gC 、大于2g 且小于3gD 、大于2g 或小于3g5、下列各式是一元一次不等式的是( )A 、0132>-+y xB 、142<xC 、x x 2213-≤+D 、0)2)(1(>+-x x6、如果232226126)43(xy y x x by y x x ax ++=--成立，则a 、b 的值为( )A 、a=3、b=2B 、a=2、b=-3C 、a=-3、b=2D 、a=-2、b=37、某同学已经抛掷硬币99次，其中50次为正面，49次为反面，则该同学第100次抛掷的结果为( )A 、正面B 、反面C 、正面或反面D 、以上都不对8、某彩票的中奖机会是1%，则下列说法中正确的是( )A 、买1张彩票一定不会中奖B 、买100张一定有1张彩票中奖C 、买100张彩票一定会中奖D 、买1张彩票可能中奖三、计算题(16分)1、)2(31)1(2+-<-x x2、⎩⎨⎧<--<+516932x x x3、))()((22y x y x y x +-+4、20004-19992×20012-1四、解答题(28分)1、梯形ABCD中，AB∥CD，AB>CD，CE∥DA，交AB于点E，且△BCE的周长为7cm，CD为3cm，求梯形ABCD的周长。
2004~2005学年第一学期期末考试流体力学与流体机械.
（2）风机的全压效率为风机的有效功率与风机的轴功率之比，即 ；风机的静压效率为风机的静压和流量的乘积与风机的轴功率之比，即
。。。。。
6．两台同型号的风机并联运行时，其流量和风压与两台单独运行的风机相比有何不同？说明原因。
答：两台同型号的风机并联运行时，其总流量等于并联机组中各台风机的流量之和，其总压头与并联机组中各台风机的压头相同；但并联机组中单台风机的
流量小于单独运行的单台风机
的流量，并联机组中单台风机的压头大于单独运行的单台风机
（2）第二自动模化区是指当流体的流量或Re数增加到某一临界数值时，粘性力的作用可以忽略不计，通道断面的流速分布规律稳定下来，不再随流体的流量增加或Re数的增大而改变。雷诺数Re的这一临界数值称为第二临界值。因为流速分布与Re值无关，说明流动进入了自动模化区，雷诺数Re大于第二临界值的自动模化区称为第二自动模化区。如圆管内紊流 的阻力平方区即为第二自动模化区。
解：已知条件：D2=500mm，b2=100mm，β2=30°，n=1250r/min，Q=8200m3/h，ρ=1.2kg/m3。
（1）
由 和 及β2绘制出口速度图如下：（4分）
（2）
所以 （4分）
5．某系列No.6风机(D2=0.6m)在最佳工况下的流量Q=9360m3/h，全风压p=1060Pa，转速n=1450r/min，现若改用该系列No.4（D2=0.4m）风机，（1）问当n=1250r/min时，最佳工况的性能参数 、 和比转数 是多少？（2*）若该风机的效率为 =70%，问轴功率 是多少？（注：附加3分）
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一、给定关系R(A,B) 和S(B,C) ，将下面的关系代数表达式转换为相应的SQL语句：
π (attribute-list) [ (condition) [ R ⋈ S ] ]
二、Megatron 747 磁盘具有以下特性：
1）有8个盘面和8192个柱面
2）盘面直径为3.5英寸，内圈直径为1.5英寸
3）每磁道平均有256个扇区，每个扇区512字节
4）每个磁道10％被用于间隙
5）磁盘转速为7200 RPM
6）磁头启动到停止需要1ms，每移动500个柱面另加1ms
回答下列有关Megatron 747的问题（要求写出式子并且计算出结果，精确到小数点后两位）：
1）磁盘容量是多少GB？
2）如果一个块是8KB，那么一个块的传输时间是多少ms？
3）平均寻道时间是多少ms？
4）平均旋转等待时间是多少ms？
三、下面是一个数据库系统开始运行后的undo/redo日志记录，该数据库系统支持simple checkpoint
设日志修改记录的格式为<Tid, Variable, New value, Old value>，（1）、（2）、（3）为三种故障情形下磁盘日志内容，请分别给出这三种情况下数据库系统的恢复过程以及数据元素A, B, C, D, E, F和G在执行了恢复过程后的值。
四、查询处理器在回答涉及R(A, B)和S(B, C)的查询“Select * From R, S Where R.B=S.B and R.B=10”时，生成了下面的逻辑查询计划：()
()S R B S B R 10
.10.==σ
σ，已知有关参数为： ● R 和S 的元组都是定长的，在磁盘块中连续存放
● T(R) = 60000，V(R, B) = 12，B(R) = 6000，T(S) =30000， V(S, B) = 5，B(S) = 1000 我们假设： 1）此查询计划中的连接实现时采用散列连接算法（非“混合散列连接”）
2）中间结果不写回磁盘 3）散列的桶存储在磁盘上 4）最终结果存放在内存中 5）有足够的内存可以执行散列连接算法 请估计此查询计划的I/O 代价。
五、我们想将关系R 按某个字段排序。
已知R 的下列信息：
• R 包含 100000 个元组，即 T(R) = 100000. • 一个磁盘块大小为 4000 bytes.
• R 的元组大小为 400 bytes ，即S(R) ＝ 400.
• 关系R 在磁盘上是连续（contiguous ）存放的，并且每个磁盘块中仅存放R 的记录 • 排序字段的大小为 32 bytes. • 记录指针的大小为 8 bytes. 回答下面的问题： （1） 如果使用两阶段归并排序，要求的最小内存是多少 （用块数表示）？ （2） 使用两阶段归并排序需要多少次磁盘I/O ？（包括最后将排序文件写回磁盘的代价） （3） 考虑下面改进的归并排序算法。
原来的两阶段归并排序的第一阶段是将排序后的整个元组写到
chunk 中，现在我们仅将排序后的 <sorting key, recordPointer> 写出。
第一阶段，我们在内存中将记录按 <sortingkey, recordPointer> 排序，当<sortingkey, recordPointer>记录填满内存时将其写到chunk 中。
第二阶段，读入各个chunk 中的 <sortingkey, recordPointer>并在内存中归并。
通过记录指针(recordPointer)我们可以读取记录的其它部分(从R 的存储块中)，并将排好序的记录写回磁盘。
这一改进的排序算法要求的最小内存是多少（用块数表示）? 排序需要多少次磁盘I/O? 在其他参数不变的情况下，当R 的元组多大时这个改进算法的I/O 代价要优于原来的归并排序算法？
（4）
⋈。