青岛科技大学826机械设计2012年考研真题
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不归零码(NRZ,Not Return to Zero)数字信号可以直接采用基带传输,所谓基带就是指基本频带。
基带传输就是在线路中直接传送数字信号的电脉冲,这是一种最简单的传输方式,近距离通信的局域网都采用基带传输。
基带传输时,需要解决数字数据的数字信号表示以及收发两端之间的信号同步问题。
对于传输数字信号来说,最简单最常用的方法是用不同的电压电平来表示两个二进制数字,也即数字信号由矩形脉冲组成。
按数字编码方式,可以划分为单极性码和双极性码,单极性码使用正(或负)的电压表示数据;双极性码是二进制码,1为反转,0为保持零电平。
根据信号是否归零,还可以划分为归零码和非归零码,归零码码元中间的信号回归到0电平,而非归零码遇1电平翻转,零时不变。
常见的几种基本的数字信号脉冲编码方案如下:单极性不归零码,无电压(也就是无电流)用来表示"0",而恒定的正电压用来表示"1"。
每一个码元时间的中间点是采样时间,判决门限为半幅度电平(即0.5)。
也就是说接收信号的值在0.5与1.0之间,就判为"1"码,如果在0与0.5之间就判为"0"码。
每秒钟发送的二进制码元数称为"码速"。
双极性不归零码,"1"码和"0"码都有电流,但是"1"码是正电流,"0"码是负电流,正和负的幅度相等,故称为双极性码。
此时的判决门限为零电平,接收端使用零判决器或正负判决器,接收信号的值若在零电平以上为正,判为"1"码;若在零电平以下为负,判为"0"码。
以上两种编码,都是在一个码元的全部时间内发出或不发出电流(单极性),以及发出正电流或负电流(双极性)。
每一位编码占用了全部码元的宽度,故这两种编码都属于全宽码,也称作不归零码NRZ (Non Return Zero)。
青岛科技大学二○一一年硕士研究生入学考试试题考试科目:机械设计注意事项:1.本试卷共5道大题(共计37个小题),满分150分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡一、是非题:正确的以“T”表示,错误的以“F”表示(每小题3分,共30分)1.螺旋传动中的螺母、滑动轴承中的轴瓦、蜗杆传动中的蜗轮,多采用青铜材料,这主要是为了提高导热能力。
2.齿轮外啮合传动中,将渐开线圆柱齿轮齿面间的凸--凸接触,改为凸--凹接触(如双圆弧齿轮),有利于提高其表面接触强度。
3.螺纹的大径,在标准中定为公称直径。
4.V带剖面中两工作面的夹角为40°,所以V带轮轮槽的工作面的夹角也是40°。
5.与滚子链相比,齿形链有传动平稳、噪声小,效率高,承受冲击载荷能力较好和轮齿受力较均匀的优点。
6.直齿圆锥齿轮强度计算中,是以大端当量直齿圆柱齿轮为计算依据的。
7.蜗杆传动的传动比等于蜗轮、蜗杆的直径比。
8.滑动轴承材料中,多孔质粉末冶金材料有自润滑性能。
9.自行车前轴属于固定心轴。
10.联轴器与离合器的主要作用是缓和冲击和振动。
二、选择填空(每小题3分,共30分)1.在机械传动中,理论上能保证瞬时传动比为常数的是。
A.带传动B.链传动C.摩擦轮传动D.齿轮传动2.运动粘度v是动力粘度η与同温下润滑油的比值。
A.密度ρB.质量mC.压力pD.速度u3.当两个被联接件都比较薄,在被联接件上宜制成通孔,通孔的加工精度要求低,结构简单,装拆方便,往往采用。
A.双头螺柱联接B.绞制孔用螺栓联接C.普通螺栓联接D.螺钉联接4.键的截面尺寸(键宽×键高)主要根据来选择。
A.轴的直径B.传递功率的大小C.轮毂的长度D.传递转矩的大小5.带传动的主要失效形式之一是带的。
青岛科技大学二○一二年硕士研究生入学考试试题考试科目:计算机网络注意事项:1.本试卷共 3 道大题(共计39 个小题),满分150 分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡一、单项选择题(每小题2分,共50分)1.UDP协议是________的传输层协议。
A、无连接的、可靠的B、面向连接的、可靠的C、面向连接的、不可靠的D、无连接的、不可靠的2.私网地址用于配置公司内部网络,下面选项中,________属于私网地址。
A、171.168.10.1B、11.15.0.1C、127.10.0.1D、192.168.0.13.在OSI模型中,第N层和其上的第N+1层的关系是________。
A、第N层为第N+1层服务B、第N+1层将从第N层接收的信息增加了一个头部C、第N层利用第N+1层提供的服务D、第N层对第N+1层没有任何作用4.对应于OSI/RM模型中的数据链路层,在IEEE 802局域网标准中,可以细分为________两层。
A、LLC、VTB、MAC、FTAM C、MAC、LLCD、LLC、FTAM 5.IP数据报穿越Internet过程中有可能被分片,在数据报被分片后,________负责IP数据报的重组。
A、源主机B、目的主机C、分片途经的路由器D、分片途经的路由器和目的主机6.在网络179.62.2.0/23中,以下哪个IP地址可以被分配给该网络的主机?A. 179.62.2.0B. 179.62.2.255C. 179.62.3.255D. 179.62.4.0 7.IP数据报从源节点到目的节点可能要经过多个网络,在传输过程中IP数据报头部中的________。
A、源IP地址和目的IP地址都不会发生变化;B、源IP地址不会发生变化,目的IP地址会发生变化;第页(共61C、源IP地址会发生变化,目的IP地址不会发生变化;D、源IP地址和目的IP地址都会发生变化;8.当PCM用于数字化语音系统时,如果将声音分为256个量化级,由于系统的采样速率为8000样本/秒,那么数据传输速率应该达到________。
青岛科技大学二○一七年硕士研究生入学考试试题考试科目:机械设计注意事项:1.本试卷共四道大题(共计28个小题),满分150分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡一、选择题(每小题3分,共30分)1.温度升高时,润滑油的粘度。
A. 随之升高B. 保持不变C.随之降低 D. 可能升高也可能降低2.在螺纹联接中,按防松原理,采用对顶螺母属于________。
A. 摩擦防松B. 机械防松C. 破坏螺旋副的关系防松D. 增大接触面积防松3.当键联接强度不足时可采用双键联接。
使用两个平键时,要求键布置。
A. 在同—直线上B. 相隔900C. 相隔1200D. 相隔18004. 带传动在工作时产生弹性滑动,是由于。
A. 包角α太小B. 初拉力F0太小C. 紧边与松边拉力不等D. 传动过载5. 用普通螺栓联接的凸缘联轴器,在传递转矩T 时,________。
A. 螺栓受剪切B.螺栓与孔壁接触面受挤压C. 螺栓同时受剪切与挤压D.螺栓受拉伸与扭转6. 带传动采用张紧装置的目的是_________。
A. 减轻带的弹性滑动B. 提高带的寿命C. 改变带的运动方向D. 调节带的初拉力7.在润滑良好的条件下,为提高蜗杆传动的啮合效率,可采用的方法为________。
A. 选择有自锁功能的蜗杆B. 减少蜗杆头数Z1C. 增加蜗杆头数Z1D. 增大蜗杆直径系数q第页(共4页)1。
青岛科技大学二○一二年硕士研究生入学考试试题考试科目:英语注意事项:1.本试卷共6道大题(共计 47 个小题),满分100 分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡PART I. READING COMPREHENSION (38%)Directions: Read the passages given below and choose the best answer to the questions attached to each of them.Passage OneQuestions 1-3 are based on the following passage.If you like the idea of staying with a family, living in house might be the answer. Good landladies---those who are superb cooks and launders, are figures as popular in fiction as the bad ones who terrorize their guest and overcharge them at the slightest opportunity. The truth is probably somewhere between the two extremes. If you are lucky, the food will be adequate, some of your laundry may be done for you and you will have a reasonable amount of comfort and companionship .For the less fortune,house rules may restrict the freedom to invite friends to visit, and shared cooking and bathroom facilities can be frustrating and row-provoking if tidy and untidy guest are living under the same roof.The same disadvantages can apply to flat sharing, with the added difficulties that arise from deciding who pays for what, and in what proportion. One person may spend hours on the phone, while another rarely makes calls. If you want privacy with guest, how do you persuade the others to go out; how do you persuade them to leave you in peace, especially if you are student and want to study?Conversely, flat sharing can be very cheap, there will always besomeone to talk to and go out with, and the chores ,in theory, can beshared.1.According to the passage ,landladies are ________ ually strict. B. always mean. C. adequately competent. D. very popular with their guest.2.What is the additional disadvantage of flat sharing ? A. Problems of sharing and paying. B. Differences in living habits. C. Shared cooking and bathroom facilities. D. Restriction to invite friends to visit.3.What is NOT mentioned as a benefit of flat sharing? A. Rent is affordable B. There is companionship. C. Housework.D. There is peace and quiet.Passage TwoQuestions 4-8 are based on the following passage. I am afraid to sleep. I have been afraid to sleep for the last few weeks.I am so tired that, finally, I do sleep, but only for a few minutes. It is not abad dream that wakes me; it is the reality I took with me into sleep . I tryto think of something else. Immediately the woman in the marketplace comes into my mind. I was on my way to dinner last night when I saw her . She was sellingskirts. She moved with the same ease and loveliness I often saw in thewomen of Laos. Her long black hair was as shiny as the black silk of theskirts she was selling. In her hair, she wore three silk ribbons, blue, green,and white. They reminded me of my childhood and how my girlfriendsand I used to spend hours braiding ribbons into our hair. I don’t know the word for “ribbons”, so I put my hand to my own hairand , with three fingers against my head , I looked at her ribbons and said “Beautiful.” She lowered her eyes and said nothing. I wasn’t sure if sheunderstood me (I don’t speak Laotian very well). I looked back down at the skirts. They add designs in them: squaresand triangles and circles of pink and green silk. They were very pretty. Idecided to buy one of those skirts, and I began to bargain with her overthe price. It is the custom to bargain in Asia. In Laos bargaining is done in soft voices and easy moves with the sort of quiet peacefulness. She smiled, more with her eyes than with her lips. She was pleased by the few words I was able to say in her language, although they were mostly numbers, and she saw that I understood something about the soft playfulness of bargaining. We shook our heads in disagreement over the price; then, immediately, we made another offer and then another shake of the head. She was so pleased that unexpectedly, she accepted the last offer I made. But it was too soon. The price was too low. She was being too generous and wouldn’t make enough money. I moved quickly and picked up two more skirts and paid for all three at the price set; that way I was able to pay her three times as much before she had a chance to lower the price for the larger purchase. She smiled openly then, and, for the first time in months, my spirit lifted. I almost felt happy. The feeling stayed with me while she wrapped the skirts in a newspaper and handed them to me. When I left, though, the feeling left, too. It was as though it stayed behind in marketplace. I left tears in my throat. I wanted to cry. I didn’t , of course. I have learned to defend myself against what is hard; without knowing it, I have also learned to defend myself against what is soft and what should be easy. I get up, light a candle and want to look at the skirts. They are still in the newspaper that the woman wrapped them in. I remove the paper, and raise the skirts up to look at them again before I pack them. Something falls to floor. I reach down and feel something cool in my hand. I move close to the candlelight to see what I have. There are five long silk ribbons in my hand, all different colors. The woman in the marketplace! She has given these ribbons to me! There is no defense against a generous spirit, and this time I cry, and very hard, as if I could make up for all the months that I didn’t cry.4. Which of the following in NOT correct?A. The writer was not used to bargaining.B. People in Asia always bargain when buying things.C. Bargaining in Laos was quiet and peaceful.D. The writer was ready to bargain with the woman.5. The writer assumed that the woman accepted the last offer mainly because womanA. thought that the last offer was reasonable.B. thought she could still make much money.C. was glad that the writer knew their way of bargaining.D. was tired of bargaining with the writer any more.6. Why did the writer finally decide to buy three skirts?A. The skirts were cheap and pretty.B. She liked the patterns on the skirts.C. She wanted to do something as compensation.D. She was fed up with further bargaining with the woman.7. When did the writer left the marketplace, she wanted to cry, but did not becauseA. she had learned to stay cool and unfeeling.B. she was afraid of crying in public.C. she had learned to face difficulties bravely.D. she had to show in public that she was strong.8. Why did the writer cry eventually when she looked at the skirts again?A. she suddenly felt very sad.B. she liked the ribbons so much.C. she was overcome by emotion.D. she felt sorry for the woman.Passage ThreeQuestions 9-14 are based on the following passage.The kids are hanging out. I pass small bands of students, in my way to work these morings. They have become a familiar part of the summer landscape.These kids are not old enough for jobs. Nor are they rich enough for camp. They are school children without school. The calendar called the school year ran out on them a few weeks ago. Once supervised by teachers and principals, they now appear to be “self care”.Passing them is like passing through a time zone. For much of our history, after all, Americans arranged the school year around the needs of work and family. In 19th-century cities, schools were open seven or eight hours a day, 11 months a year. In rural America, the year was arranged around the growing season. Now, only 3 percent of families follow the agricultural model, but nearly all schools are scheduled as if our children went home early to milk the cows and took months off to work the crops. Now, three-quarters of the mothers of school-age children work, but the calendar is written as if they were home waiting for the school bus.The six-hour day, the 180-day school year is regarded as something holy. But when parents work an eight-hour day and a 240-day year, it means something different. It means that many kids go home to empty houses. It means that, in the summer, they hang out. “We have a huge mismatch between the school calendar and realities of family life,” says Dr. Ernest Boyer, head of the Carnegie Foundation for the Advancement of Teaching.Dr. Boyer is one of many who believe that a radical revision of the school calendar is inevitable."School, whether we like it or not, iseducational. It always has been.”His is not popular idea. School are routinely burdened with the job of solving all our social problems. Can they be asked to meet the needs of our work and family lives?It may be easier to promote a linger school year on its educational merits and, indeed, the educational case is compelling. Despite the complaints and studies about our kids’ lack of learning, the United State still has a shorter school year than any industrial nation. In most of Europe, the school year is 220 days. In Japan, it is 240 days long. While classroom time alone doesn’t produce a well-educated child, learning takes time and more learning takes more time. The long summers of forgetting take a toll.The opposition to a longer school year comes from families that want to and can provide other experiences for their children. It comes from teachers. It comes from tradition. And surely from kids. But the most important part of the conflict has been over the money.9. Which of the following is an opinion of the author’s?A."The kids are hanging out.”B."They are school children without school.”C."These kids are not old enough for jobs.”D. “The calendar called the school year ran out on them a few weeks ago.”10. The current American school calendar was developed in the 19th century according toA. the growing season on nation’s form.B. the labor demands of the industrial age.C. teachers’ demands for more vacation time.D. parents’ demands for other experiences for their kids.11. The author thinks that the current school calendarA. is still valid.B. is out of date.C. can not be revised.D. can not be defended.12. Why was Dr. Boy’s idea unpopular?A. He argues for the role of school in solving social problems.B. He supports the current school calendar.C. He thinks that school year and family life should be considered separately.D. He strongly believes in the educational role of school.13. “The long summers of forgetting take a toll ”in the last paragraph but one means thatA. long summer vacation slows down the progress go learning.B. long summer vacation has been abandoned in Europe.C. long summers result in less learning time.D. long summers are a result of tradition.14. The main purpose of the passage isA. to describe how American children spend their summer.B. to explain the needs of the modern working families.C. to discuss the problems of the current school calendar.D. to persuade parents to stay at home to look after their kids. Passage FourQuestions 15-19 are based on the following passage.Women's minds work differently from men's. At least, that is what most men are convinced of. Psychologists view the subject either as a matter of frustration or a joke. Now the biologists have moved into this minefield, and some of them have found that there are real differences between the brains of men and women. But being different, they point out hurriedly, is not the same as being better or worse.There is, however, a definite structural variation between the male and female brain. The difference is in a part of the brain that is used in the most complex inte11ectual processes-the link between the two halves of the brain.The two halves are linked by trunkline of between 200 and 300 million nerves, the Corpus callosum. Scientists have found quite recently that the Corpus callosum in women is always larger and probably richer in nerve fibers than it is in men. This is the first time that a structural difference has been found between the brains of women and men and it must have some significance. The question is "What?", and, if this difference exists, are there others? Research shows that present-day women think differently and behave differently from men. Are some of these differences biological and inborn, a result of evolution? We tend to think that is the influence of society that produces these differences. But could we be wrong?Research showed that these two halves of the brain had different functions, and that the Corpus callosum enabled them to work together. For most people, the left half is used for word - handling, analytical and logical activities; the right half works on pictures, patterns and forms. We need both halves working together. And the better the connections, the more harmoniously the two halves work. And, according to research findings, women have the better connections.But it isn't all that easy to explain the actual differences between skills of men and women on this basis. In schools throughout the world girls tend to be better than boys at“language subjects”and boys better at maths and physics. If these differences correspond with the differences in the hemispheric trunkline, there is an unalterable distinction between the sexes.We shan't know for a while, partly because we don't know of any precise relationship between abilities in school subjects and the functioning of the two halves of the brain ,and we cannot understand how the two halves interact via the corpus callosum. But this striking difference must have some effect and, because the difference is in the parts of the brain involved in intellect, we should be looking for differences in intellectual processing.15. Which of the fo11owing statements is CORRECT?A. Biologists are conducting research where psychologists have given up.B. Brain differences point to superiority of one sex over the other.C. Results of scientific research fail to support popular belief.D. The structural difference in the brain between the sexes has long been known.16. According to the passage it is commonly believed that brain differences are caused by ________ factors.A. biologicalB .psychologicalC. physicalD .social17."these differences" in paragraph 5 refer to those inA. skills of men and women.B. school subjects.C. the brain structure of men and women.D. activities carried out by the brain.18. At the end of the passage the author proposes more work onA. the brain structure as a whole.B. the functioning of part of the brain.C. the distinction between the sexes.D. the effects of the corpus callosum.19. What is the main purpose of the passage?A. To outline the research findings on the brain structure.B. To explain the link between sex and brain structure.C. To discuss the various factors that cause brain differences.D. To suggest new areas in brain research.PART II CLOZE (15%)Directions: Choose a proper word from the list to fill in each blank in the following passage. Change the form of the word if necessary. base create evoke suffice handdeeply poorly dispose degree dependvary religious present movement endeavorEverything that the human race has done and thought is concerned with the satisfaction of (1)__________ felt needs and the assuagement of pain. One has to deep this constantly in mind if one wishes to understand spiritual (2)___________ and their development. Feeling and longing are the motive force behind all human (3)___________ and human creation, in however exalted a guise the latter may (4)__________ themselves to us. Now what are the feelings and needs that have led men to(5)__________ thought and belief in the widest sense of the words? A little consideration will (6)___________ to show us that the most(7)___________ emotions preside over the birth of religious thought and experience. With primitive man it is above all fear that (8)__________ religious notions—fear of hunger, wild beasts, sickness, death. Since at this stage of existence understanding of causal connections is usually (9)__________ developed, the human mind (10)__________ illusory beings more or less analogous to itself on whose wills and actions these fearful happenings (11)___________. Thus one tries to secure the favor of these beings by carrying out actions and offering sacrifices which, according to the tradition (12)_________ down from generation to generation, propitiate them or make them well (13)___________ toward a mortal. In this sense I am speaking of a religion of fear. This, though not created, is in an important (14)___________ stabilized by the formation of a special priestly caste which sets itself up as a mediator the people and the beings they fear, and erects a hegemony on this (15)________. PART III TRANSLATION (15%)(I).Translate the following into Chinese:(10%)1. This discovery suggests that life is probably a pretty ordinary phenomenon that occurs any place you give it half a chance.2. But I find it helpful to consider what might have happened in my own marriage if a copy of me had been made to overcome infertility.3. Forty years after the Wright Brothers’ first flight, by contrast, commercial air travel was a dauntingly expensive but widespread and growing industry.4. The promissory notes of well-known individuals and bills of exchangedrawn on English merchants readily exchanged hands for severalmonths.5.When the demand becomes immoderate, consumption of drugs increases and the incidence of adverse effects and waste follows suit.(II). Translate the following into English (5%)随着1997年许多东亚国家经济中出现的戏剧性的货币贬值,这些国家遭受了急剧而且徘徊不去的经济衰退。
青岛科技大学二○一一年硕士研究生入学考试试题考试科目:机械设计注意事项:1.本试卷共5道大题(共计37个小题),满分150分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡一、是非题:正确的以“T”表示,错误的以“F”表示(每小题3分,共30分)1.螺旋传动中的螺母、滑动轴承中的轴瓦、蜗杆传动中的蜗轮,多采用青铜材料,这主要是为了提高导热能力。
2.齿轮外啮合传动中,将渐开线圆柱齿轮齿面间的凸--凸接触,改为凸--凹接触(如双圆弧齿轮),有利于提高其表面接触强度。
3.螺纹的大径,在标准中定为公称直径。
4.V带剖面中两工作面的夹角为40°,所以V带轮轮槽的工作面的夹角也是40°。
5.与滚子链相比,齿形链有传动平稳、噪声小,效率高,承受冲击载荷能力较好和轮齿受力较均匀的优点。
6.直齿圆锥齿轮强度计算中,是以大端当量直齿圆柱齿轮为计算依据的。
7.蜗杆传动的传动比等于蜗轮、蜗杆的直径比。
8.滑动轴承材料中,多孔质粉末冶金材料有自润滑性能。
9.自行车前轴属于固定心轴。
10.联轴器与离合器的主要作用是缓和冲击和振动。
二、选择填空(每小题3分,共30分)1.在机械传动中,理论上能保证瞬时传动比为常数的是。
A.带传动B.链传动C.摩擦轮传动D.齿轮传动2.运动粘度v是动力粘度η与同温下润滑油的比值。
A.密度ρB.质量mC.压力pD.速度u3.当两个被联接件都比较薄,在被联接件上宜制成通孔,通孔的加工精度要求低,结构简单,装拆方便,往往采用。
A.双头螺柱联接B.绞制孔用螺栓联接C.普通螺栓联接D.螺钉联接4.键的截面尺寸(键宽×键高)主要根据来选择。
A.轴的直径B.传递功率的大小C.轮毂的长度D.传递转矩的大小5.带传动的主要失效形式之一是带的。
考生答题须知1.所有题目(包括填空、选择、图表等类型题目)答题答案必须做在考点发给的答题纸上,做在本试题册上无效。
请考生务必在答题纸上写清题号。
2.评卷时不评阅本试题册,答题如有做在本试题册上而影响成绩的,后果由考生自己负责。
3.答题时一律使用蓝、黑色墨水笔或圆珠笔作答(画图可用铅笔),用其它笔答题不给分。
4.答题时不准使用涂改液等具有明显标记的涂改用品。
一、是非题:正确的以“T”表示,错误的以“F”表示(每小题1.5分,共15分)1.机械零件的强度、刚度等性能通常采用额定载荷进行计算。
()2.在变应力作用下,零件的主要失效形式是疲劳断裂,而在静应力作用下,其主要失效形式是塑性变形或断裂。
()3.齿面点蚀失效在开式齿轮传动中不常发生。
()4.齿向载荷分布系数K与齿轮制造精度、装配误差以及轴、轴承和基座等的变形有关。
()5.单线螺纹多用于连接,多线螺纹多用于传动。
()6.受轴向变载荷的普通螺栓紧连接中,在被连接件之间加入橡胶垫片,可以提高螺栓的疲劳强度。
()7.平键是靠上下两面与键槽间的摩擦力传递载荷的。
()8.设计V带传动时如发现带的根数过多可选用更大截面型号的V带来解决。
()9.蜗杆传动变位后,蜗轮的分度圆和节圆仍旧重合,但蜗杆的节线与分度线不再重合。
()10.链条节距越大,链轮齿数越多,链传动的动载荷也就越大。
()二、选择填空(每小题3分,共30分)1. 直齿圆柱齿轮传动,当保持齿轮的直径不变而减小模数时,可以。
A.提高轮齿的接触强度B.提高轮齿的静强度C.改善传递的平稳性D.提高轮齿的弯曲强度2. 蜗杆传动热平衡计算的目的是为了控制温升,防止。
A.蜗杆力学性能下降B.润滑油变质和胶合C.传动效率下降D.蜗轮材料退火3. 既有齿轮传动又有蜗杆传动时,某人认为把蜗杆传动放在高速级有以下优点:(1)提高传动效率,(2)节省贵重的有色金属,(3)减少作用在蜗杆上的轴向力,(4)降低齿轮的制造精度,(5)使整个传动装置结构紧凑。
青岛科技大学2005年研究生入学考试试题考试科目: 机械设计(A 卷)(答案全部写在答题纸上)一、选择填空(每小题2分,共20分)1.蜗杆传动中,轮齿承载能力计算,主要是针对 来进行的。
A) 蜗杆齿面接触疲劳强度和蜗轮齿根弯曲疲劳强度B) 蜗轮齿面接触疲劳强度和蜗杆齿根弯曲疲劳强度C) 蜗杆齿面接触疲劳强度和齿根弯曲疲劳强度D) 蜗轮齿面接触疲劳强度和齿根弯曲疲劳强度2.齿轮传动的动载荷系数中,动载荷系数v K 的大小主要与 有关。
A) 制造精度 B) 齿轮模数 C) 端面重合度 D) 轮齿宽度3.滚动轴承基本额定动载荷所对应的基本额定寿命是 。
A) 710; B) 2.5×710 C) 610 D)5×6104.当轴上安装的零件要承受轴向力时,采用 来进行轴向定位,所能承受的轴向力较大。
A) 圆螺母 B) 紧定螺钉 C) 弹性挡圈5.离合器与联轴器的不同点为 。
A) 过载保护 B) 可以将两轴的运动和载荷随时脱离和接合C) 补偿两轴间的位移6.滚动轴承的内外圈及滚动体的表面硬度为 ;软齿面齿轮的齿面硬度为 。
A) 150HBS B)(20~32)HBS C) ≤350 HBS D) (60~65)HRC7. 某轴材料为45钢,两支点采用深沟球轴承支承,验算时发现轴的刚度不够,这时应 。
A )改为合金钢轴B )改为滚子轴承 C) 增加轴径 D) 改为滑动轴承8.带传动采用张紧轮的目的是 。
A) 调节带的初拉力 B) 提高带的寿命C) 改变带的运动方向 D) 减轻带的弹性滑动9.圆锥齿轮为了测量和计算方便标准模数取在 ,受力分析时模数取在 。
A) 分度圆锥面 B) 轮齿大端 C) 齿宽中点 D)锥距中点10.当采用铰制孔用螺栓联接承受横向载荷时,螺栓杆受到 作用。
A) 剪切和挤压 B )拉伸和剪切 C) 弯曲和挤压 D) 扭转和弯曲二、填空题(每空1分,共25分)1.在普通平健联接中,平健的工作面是 ,其最主要的失效形式是 ,平健的剖面尺寸(h b ⨯)按 从标准中选取。
青岛科技大学二○一二年硕士研究生入学考试试题考试科目:基础英语注意事项:1.本试卷共四道大题(共计60 个小题),满分 150 分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡Part I Vocabulary and Grammar. Fill in the blank with the word or phrase that you think is the most appropriate from the four choices given below. (30 points)1. The manager vowed to revenge the ______ insult of his competing counterpart yesterday.A. calculatedB. outrageousC. intentionedD. selfish2. Almost any solid ______ can be called dust if it is light enough to float in the air.A. wasteB. spotC. MetalD. speck3. We heard wolves ______ mournfully somewhere nearby in the complete darkness when we camped in the forest last weekend.A. barkingB. roaringC. howlingD. growling4. The sweater he bought last week ______ after he washed it.A. shrankB. shortenedC. decreasedD. lessened5. As a result of sluggish business, the boss of the company is urging his clerks to be ______ with electricity.A. economicsB. economicalC. stingyD. thrifty6. The minister has to provide a very ______explanation for the new medical care reform.A. compulsoryB. comprehensiveC. sophisticatedD. understanding7. They sell their military equipment to whoever needs it with the ______ purpose of making profit.A. onlyB. uniqueC. singularD. sole8. No one believed that such a little girl could ______ the things well ahead.A. reconcileB. suspectC. forsakeD. anticipate9. Tom’s lecture was careful and ______ but his words did not seem to make much sense.A. distinctB. distinguishedC. distinguishableD. distinctive10. The most ______ of all Olympic events is the decathlon (a sports competition with 10different events).A. creativeB. excitedC. gruesomeD. grueling11. As it ______ the effects of high temperatures, rhenium is a valuable ingredient in certain alloys.A. resists B withholds C. reduces D. discharges12. In ancient China, thunder was believed to be a manifestation of the______ of the gods.A. spiritB. powerC. wrathD. sorrow13. The African quality of his music is ______ in the art that people of his generation enjoyed.A. inbornB. ingrainedC. impregnatedD. included14. I am in no ______ this evening to listen to his silly jokes.A. feelingB. attitudeC. moodD. tendency15. The young scientist became known for his ______ into the distribution of the wild species in this part of the region.A. examinationB. expositionC. researchD. account16. As soon as World War II ended, Einstein urged that atomic energy______ to peaceful uses.A. be putB. is putC. will be putD. would be put17. You ______ the washing-up. I would have dong it for you.A. needn’t have doneB. didn’t need to have doneC. weren’t toD. mustn’t have done18. The professor is very busy ______ for the examination now. Please come again at some other time.A. preparingB. preparedC. being preparedD. to prepared19. Next time we go house-hunting, remember ______ the agent for very clear directions. I wasted hours ______ the last house.A. to ask; to look forB. to ask; looking forC. asking; looking forD. asking; to look for20. It is a common expression to characterize something as “light as air”, but air is ______ “light”.A. soB. ratherC. hardlyD. somewhat21. The stout fellow over there is ______ the great magician Charlie Steward, himself.A. no other thanB. none other thanC. no other thanD. no one but22. In the new movie she wore, ______ was very uncommon in the country, a scarlet coat.A. whatB. thatC. of whatD. the23. Robinson Crusoe was hungry ______ human companionship.A. forB. aboutC. ofD. with24. Among all the students in this class, Tony is the quickest one ______ figures.A. toB. forC. inD. at25. I’m very hopeful ______ passing the course.A. forB. aboutC. inD. on26. He was laid ______ for six weeks with two broken ribs.A. awayB. downC. byD. up27. The population ______ their flags to celebrate the return of their victorious team.A. hung outB. hung togetherC. hung behindD. hung over28. As a citizen it is important to ______ with your neighbors.A. keep inB. keep offC. keep outD. keep on29. The government has ______ new measures to combat inflation.A. brought inB. brought aboutC. brought onD. brought up30. The idea of a balanced diet is very difficult to ______ to anyone who knows little about food values.A. put throughB. put acrossC. take inD. make overPart II Reading Comprehension (40 points)Read the following essay carefully, and then, answer the questions in Section A, B, C, and D.How to Avoid Foolish Opinions1To avoid the various foolish opinions to which mankind is prone, no superhuman genius is required. A few simple rules will keep you, not from all errors, but from silly ones.2If the matter is one that can be settled by observation, make it yourself. Aristotle could have avoided the mistake of thinking that women have fewer teeth than men by simply asking Mrs. Aristotle to keep her mouth open while he counted. He did not do so because he thought he knew. Thinking that you know when in fact you don’t is a fatal mistake, to which we are all prone. I believe hedgehogs eat black beetles, because I have been told that they do; but if I were writing a book on the habits of hedgehogs, I shouldn’t commit myself until I had seen one enjoying this unappetizing diet. Aristotle, however, was less cautious. Ancient and medieval authors knew all about unicorns and salamander; not one of them thought it necessary to avoid dogmatic statements about them because he had never seen one of them.3Many matters, however, are less easily brought to the test of experience. If you have passionate convictions on many such matters, there are ways in which you can make yourself aware of your own bias. If an opinion contrary to your own makes you angry, that is a sign that you are subconsciously aware of having no good reason for thinking as you do. If someone maintains that two and two are five, or that Iceland is on the equator, you feel pity rather than anger, unless you know so little of arithmetic or geography that his opinion shakes your own contrary conviction. The most savage controversies are those about matters as to which there is no good evidence either way.Persecution is used in theology, not in arithmetic, because inarithmetic there is knowledge, but in theology there is only opinion.So whenever you find yourself getting angry about a difference of opinion, be on guard; you’ll probably find, on examination, that your belief is going beyond what the evidence warrants.4 A good way of riding yourself of certain kinds of dogmatism is tobecome aware of opinions held in social circles different from yours.When I was young, I lived much outside my own country, and I found this very profitable in diminishing the intensity of insular prejudice. If you can’t travel, seek out people with whom you disagree, and read a newspaper belonging to a party that is not yours. If the people and the newspaper seem mad, perverse, and wicked, remind yourself that you seem so to them. In this opinion both parties may be right, but they can’t both be wrong. This reflection should generate a certain caution. 5For those who have enough psychological imagination, it is a good plan to imagine an argument with a person having a different bias.This has one advantage: the method is not subject to the same limitations of time and space. Mahatma Gandhi deplored railways and steamboats and machinery; he would have liked to remove the effect of the whole of the industrial revolution. You may never have an opportunity of actually meeting any one who holds this opinion, because in Western countries most people take the advantages of modern technique for granted. But if you want to make sure you are right in agreeing with the prevailing opinion, you’ll find it a good plan to test the arguments that occur to you by considering what Gandhi might have said in refutation of them. I have sometimes been led actually to change my mind as a result of this kind of imaginary dialogue, and short of this, I have frequently found myself growing less dogmatic and cocksure through realizing the possible reasonableness of a hypothetical opponent.6Be very wary of opinions that flatter your self-esteem. Both men and women, nine times out of ten, are firmly convinced of the superior excellence of their own sex. There is abundant evidence on both sides.If you are a man, you can point out that most poets and men of science are male; if you are a woman, you can retort that so are mostcriminals. The question is inherently insoluble, but self-esteem conceals this from most people. We are all persuaded that our own nation is superior to others. Seeing that each nation has it characteristic merits and demerits, we adjust our standard of values so as to make out that the merits possessed by our nation are the really important ones, while its demerits are comparatively trivial. Here, again, the rational man will admit that the question is one to which there is no demonstrably right answer. It is more difficult to deal with the self-esteem of man as man, because we cannot argue out the matter with some non-human. The only way I know of dealing with this general human conceit is to remind ourselves that man is a brief episode in the life of a small planet in a little corner of the universe, and that for aught we know, other parts of the cosmos may contain beings as superior to ourselves as we are to jelly-fish.Section A. Answer the following questions. (15%)31. The title of this essay is an adaptation of a phase from its first paragraph. Is there any other phrase in the first paragraph which could be used to make up a good title for the essay? If so, what is it?32. What are the “simple rules” which the author suggests in his essay? What are the examples does the author use to illustrate his rules respectively?33. What, in the author’s opinion, is the difference between knowledge and opinion?34. There is one statement in Para. 2 which is ironical, i.e. it means the opposite of what it appears. What is the statement?35. “The author’s main point is that we should not believe strongly in anything.” Is this correct? If so, why do you agree with the author? If not, how would you change the statement?Section B. Read the short extract given below and answer the questions by choosing the best alternative (a, b, c, d) under each. (10%)“If an opinion contrary to your own makes you angry, that is a sign that you are subconsciously aware of having no good reason for thinking as you do. If someone maintains that two and two are five, or that Iceland ison the equator, you feel pity rather than anger, unless you know so little of arithmetic or geography that his opinion shakes your own contrary conviction.”36. The second sentence_____________(a) simply adds a further point to the argument already stated in the first sentence.(b) illustrates the point made in the first sentence.(c) builds up the argument of the first sentence by restating it from the opposite point of view.(d) makes the main point which has only been introduced by the first sentence.37. If someone else’s opinion makes us angry, it means that____________(a) our own opinion is not based on good reasons and we know this subconsciously.’(b) we are not consciously aware of having no good reason for becoming angry.(c) we are subconsciously aware of having no good reason for becoming angry.(d) there may be good reasons for his opinion but we are not consciouslyaware of them.38. The author mentions arithmetic and geography because____________(a) we should know both subjects in order to avoid foolish opinions.(b) many foolish opinions and unnecessary arguments occur in those two subjects.(c) the two opinions he has mentioned already have to do with those subjects.(d) he himself is very knowledgeable about those two subjects.39. “… your own contrary conviction” refers to ____________(a) the opinion that two and two are five and that Iceland is on the equator.(b) the fact that you know so little about arithmetic or geography.(c) the fact that you feel pity rather than anger.(d) the opinion that two and two are four and that Iceland is a long way from the equator.40. The main point of these two sentences is ____________(a) that we should feel pity rather than anger when someone disagree with us.(b) that we shouldn’t be angry with people who hold foolish opinions.(c) that one way of avoiding foolish opinions is to feel pity rather than anger.(d) that we can test our own opinion by finding out whether we feel pity or anger when someone disagrees with us.Section C. Find single words or phrases in this essay which have roughly the meanings given below. (10%)41. conscious of42. narrow-minded43. regretted the existence of44. good opinion of oneself45. ending in death or disaster46. making yourself free from47. prejudice48. thinking too highly of oneself49. unreasonable; wrong50. feel unhappy about; dislikeSection D. Match the words given under List A with the meanings given under List B. List B has some extra items. (5%)A B51. inherently (a) fierce; cruel52. episode (b) quite certain53. retort (c) answer back quickly54. cosmos (d) inside55. persecution (e) fashionable56. savage (f) unreasonable punishment57. cocksure (g) instinctively58. prevailing (h) one event in a series of events59. subconsciously (i) careful60. wary (j) going to a court of law(k) by its very nature(l) power; snow(m) universePart III Translation (50 points)Section A. Translate the following passage into English. (25%)笔者日前买了台电脑,喜滋滋地上网交友。
青岛科技大学二○一二年硕士研究生入学考试试题考试科目:英语综合考试Ⅰ注意事项:1.本试卷共6道大题(共计12个小题),满分150分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡PART I LINGUISTICS (60 points)Section I Define the following terms (20 points)Give the definition of each term in no less than 50 words.1. paradigmatic relations2. displacement3. dialect4. applied linguisticsSection II Essay questions (40 points)Answer each of the following questions in no less than 100 words.1.What is cohort theory?2.What is speech act theory?3.What does Chomsky mean by Language Acquisition Device?4. What is the difference between langue and parole?PART II TRANSLATION (60 points)Section I Translate the following passage into Chinese (20 points) Resignation is of two sorts, one rooted in despair, the other in unconquerable hope. The man who has suffered such fundamental defeat that he has given up hope of serious achievement may learn the resignation of despair, and if he does, he will abandon all serious activity. He may camouflage his despair by religious phrases, or bythe doctrine that contemplation is the true end of man, but whatever disguise he may adopt to conceal his inward defeat, he will remain essentially useless and fundamentally unhappy. The man whose resignation is based on unconquerable hope acts in quite a different way. Hope which is to be unconquerable must be large and impersonal. Whatever my personal activities, I may be defeated by death, or by certain kinds of diseases; I may be overcome by my enemies; I may find that I have embarked upon an unwise course which cannot lead to success. In a thousand ways the failure of purely personal hopes may be unavoidable, but if personal aims have been part of larger hopes for humanity, there is not the same utter defeat when failure comes.--From “On Resignation” by Bertrand RussellSection II Translate the following passage into English (20 points)阳光滑到玻璃板上。
得到拟录取消息的前些天一直忐忑不安,想象着自己失败时的沮丧或者自己成功时的兴奋。
终于尘埃落定,内心激动,又面色平静地拿起手机给每一个关心我的家人和朋友发了这个好消息。
也想在这里写下自己考研路上的点点滴滴,给自己留一个纪念,也希望大家能从中得到一些收获。
立大志者得中志,立中志者得小志,立小志者不得志。
所以我建议刚开始大家就朝着自己喜欢的,最好的学校考虑,不要去担心自己能不能考上的问题,以最好的学校的标准来要求自己去学习。
大家可以去自己想报考的学校官网上下过去的录取分数线,报录比之类的信息给自己一个参考和努力目标。
包括找一些学长学姐问下经验也是很有用的。
备考那个时候无论是老师还是同学们都给了我很多的帮助,让我在备考的路上少走了很多的弯路,尤其是那些珍贵的笔记本,现在回想起来依然很是感动,还好现在成功上岸,也算是没有辜负大家对我的期望。
所以想着成功之后可以写一篇经验贴,希望可以帮助大家。
话不多说,下面跟大家介绍一下我的经验吧。
文末有笔记和真题下载,大家可自取。
青岛科技大学机械专硕的初试科目为:(101)思想政治理论(204)英语二(302)数学二和(825)材料力学或(826)机械设计参考书目为:1.《材料力学》刘鸿文主编高等教育出版社2009跟大家先说一下英语的复习吧。
学英语免不了背单词这个难关,词汇量上不去,影响的不仅是考试成绩,更是整体英语能力的提升;背单词也是学习者最感到头痛的过程,不是背完了转身就忘,就是背的单词不会用,重点单词主要是在做阅读的时候总结的,我把不认识不熟悉的单词全都挑出来写到旁边,记下来反复背直至考前,总之单词这一块贵在坚持,背单词的日程一定要坚持到考研前一天。
因此,学会如何高效、科学地记忆词汇,养成良好的记单词习惯,才能达到事半功倍的学习效果,我用的是《木糖英语单词闪电版》,里面的高频词汇都给列出来了,真的挺方便的,并且刷真题我用的《木糖英语真题手译》这本书,我感觉对我帮助特别大,里面的知识点讲解的通俗易懂,而且给出的例子都很经典,不容易忘记。
青岛科技大学二○一二年硕士研究生入学考试试题考试科目:安全系统工程注意事项:1.本试卷共 6 道大题(共计 23 个小题),满分 150 分;2.本卷属试题卷,答题另有答题卷,答案一律写在答题卷上,写在该试题卷上或草纸上均无效。
要注意试卷清洁,不要在试卷上涂划;3.必须用蓝、黑钢笔或签字笔答题,其它均无效。
﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡﹡一、名词解释(每题5分,共20分)1.系统安全2. 安全检查表3. 安全评价4. 事件树分析二、选择题(每题2分,共20分)1、决策树法是一种()性方法。
A 演绎B 归纳C 综述D 经验2、稀少事件是指那些()的事件。
A 事故后果很大B 事故后果可以忽略C 发生的概率非常小的“百年不遇”D 肯定发生3、所谓割集指的是:事故树中某些基本事件的集合,当这些基本事件都()时,顶上事件必然()。
[A] 发生,发生 [B] 发生,不发生 [C] 成功,失败 [D]失败,成功4、故障模式及影响分析的英文缩写是()。
[A] FIFA [B] FAEC [C] FEAC [D] FMEA5、当事故发生概率不太大和不太小时,应当采用()来评价安全性。
A 绝对风险B 对比风险C 事故后果 D经济损失6、事件树分析中在事故发展过程中出现的事件有()种状态。
A 1B 2C 3D 47、定量计算事故树顶上事件发生概率时一般假设事故树中的基本事件为()。
A 不相容事件B 互为逆事件C 必然发生事件D 相互独立事件8、概率设计方法的基本思想是按零件的失效概率的大小来衡量零件的可靠性,其理论基础是()。
A 应力-应变原理B 冗余设计原理C 应力-强度“干涉”原理D 相互独立原理9、事故树中两个基本事件的状态以X1,X2来表示,则由这两个基本事件为输入事件构成的与门的输出事件的状态可以由()函数来表达。
A min(X1,X2)B max(X1,X2)C X1+X2D X1—X210、可以将()看作是一个‘信号’传送器,把()看作是一个‘信号’发生器。