传感器课后习题参考答案2011-9-26
传感器原理及应用课后习题答案(吴建平)
传感器原理及应用课后习题答案吴建平第1章概述1.1 什么是传感器？按照国标定义，“传感器”应该如何说明含义？1.2 传感器由哪几部分组成？试述它们的作用及相互关系。
1.3 简述传感器主要发展趋势，并说明现代检测系统的特征。
1.4 传感器如何分类？按传感器检测的范畴可分为哪几种？1.5 传感器的图形符号如何表示？它们各部分代表什么含义？应注意哪些问题？1.6 用图形符号表示一电阻式温度传感器。
1.7 请例举出两个你用到或看到的传感器，并说明其作用。
如果没有传感器，应该出现哪种状况。
1.8 空调和电冰箱中采用了哪些传感器？它们分别起到什么作用？答案：1.1答：从广义的角度来说，感知信号检出器件和信号处理部分总称为传感器。
我们对传感器定义是：一种能把特定的信息（物理、化学、生物）按一定规律转换成某种可用信号输出的器件和装置。
从狭义角度对传感器定义是：能把外界非电信息转换成电信号输出的器件。
我国国家标准（GB7665—87）对传感器（Sensor/transducer）的定义是：“能够感受规定的被测量并按照一定规律转换成可用输出信号的器件和装置”。
定义表明传感器有这样三层含义：它是由敏感元件和转换元件构成的一种检测装置；能按一定规律将被测量转换成电信号输出；传感器的输出与输入之间存在确定的关系。
按使用的场合不同传感器又称为变换器、换能器、探测器。
1.2答：组成——由敏感元件、转换元件、基本电路组成；关系，作用——传感器处于研究对象与测试系统的接口位置，即检测与控制之首。
传感器是感知、获取与检测信息的窗口，一切科学研究与自动化生产过程要获取的信息都要通过传感器获取并通过它转换成容易传输与处理的电信号，其作用与地位特别重要。
1.3答：（略）答：按照我国制定的传感器分类体系表，传感器分为物理量传感器、化学量传感器以及生物量传感器三大类，含12个小类。
按传感器的检测对象可分为：力学量、热学量、流体量、光学量、电量、磁学量、声学量、化学量、生物量、机器人等等。
2011年硕士研究生入学考试2011英语二真题及参考答案
2011年硕士研究生入学考试2011英语二 真题及参考答案Section I Use of EnglishDirections ：Read the following text. Choose the best word(s) for each numbered black and mark A, B, C or D on ANSWER SHEET 1. (10 points)The Internet affords anonymity to its users, a blessing to privacy and freedom of speech. But that very anonymity is also behind the explosion of cyber-crime that has 1 across the Web. Can privacy be preserved 2 bringing safety and security to a world that seems increasingly 3 ?Last Last month, month, month, Howard Howard Howard Schmidt, Schmidt, Schmidt, the the the nation nation ’s s cyber-czar, cyber-czar, offered the federal federal government governmenta 4 to make the Web a safer place-a“voluntary trusted identity ” system that would be the high-tech 5 of a physical key, a fingerprint and a photo ID card, all rolled 6 one. The system might use a smart identity card, or a digital credential 7 to a specific computer .and would authenticate users at a range of online services.The idea is to 8 a federation of private online identity systems. User could 9 which system to join, and only registered users whose identities have been authenticated could navigate those systems. The approach contrasts with one that would require an Internet driver ’s license 10 by the government.Google and Microsoft are among companies that already have these that already have these““single sign-on ” systems that make it possible for users to 11 just once but use many different services.12 .the approach would create a “walled garden ” n cyberspace, with safe“neighborhoods” and bright “streetlights ” to establish a sense of a 13 community.Mr. Schmidt described it as a “voluntary ecosystem ” in which “individuals and organizations can complete online transactions with 14 ,trusting the identities of each other and the identities of the infrastructure 15 which the transaction runs ”.Still, the administration ’s plan has 16 privacy rights activists. Some applaud the approach; others are concerned. It seems clear that such a scheme is an initiative push toward what would 17 be a compulsory Internet “drive ’s license ” mentality.The plan has also been greeted with 18 by some computer security experts, who worry that the “voluntary ecosystem ” envisioned by Mr. Schmidt would still leave much of the Internet 19 .They argue that all Internet users should be 20 to register and identify themselves, in the same way that drivers must be licensed to drive on public roads.1．A.sweptB.skipped B.skippedC.walkedD.ridden 2． A.for B.within C.while D.though 3．A.carelesswlessC.pointlessD.helpless 4．A.reasonB.reminderpromiseD.proposal 5．rmationB.interferenceC.entertainmentD.equivalent 6．A.byB.intoC.fromD.over 7．A.linkedB.directedC.chainedpared 8． A.dismiss B.discover C.create D.improve9． A.recall B.suggestC.selectD.realize 1010．． A.relcased B.issuedC.distributedD.delivered 1111．． A.carry on B.linger onC.set inD.log in 1212．． A.In vain B.In effectC.In returnD.In contrast 1313．． A.trusted B.modernizedc.thriving peting 1414．． A.caution B.delightC.confidenceD.patience 1515．． A.on B.afterC.beyondD.across 1616．． A.divided B.disappointedC.protectedD.united 1717．． A.frequestly B.incidentallyC.occasionallyD.eventually 1818．． A.skepticism B.relerance C.indifference D.enthusiasm 1919．． A.manageable B.defendableC.vulnerableD.invisible 2020．． A.invitedB.appointedC.allowedD.forced S ection II Reading ComprehensionPart AD irections:Read the following four texts. Answer the questions after each text by choosing A, B,C or D. Mark your answers on ANSWER SHEET 1. (40points)Text 1Ruth Simmons joined Goldman Sachs ’s board as an outside director in January 2000: a year later she became president of Brown University. For the rest of the decade she apparently managed both roles without attracting much eroticism . But by the end of 2009 Ms. Simmons was under fire for having sat on Goldman ’s compensation committee; how could she have let those enormous bonus payouts pass unremarked? By February the next year Ms. Simmons had left the board. board. The The position position was was just taking up too much time, she said.Outside directors are supposed to serve as helpful, yet less biased, advisers on a firm ’s board. Having made their wealth and their reputations elsewhere, they presumably have enough independence to disagree with the chief executive ’s proposals. If the sky, and the share price is falling, outside directors should be able to give advice based on having weathered their own crises.The researchers from Ohio University used a database hat covered more than 10,000 firms and more than 64,000 different directors between 1989 and 2004. Then they simply checked which directors stayed from one proxy statement to the next. T he most likely reason for departing a board was age, so the researchers concentrated on those “surprise ” disappearances by directors under the age of 70. They fount that after a surprise departure, the probability that the company will subsequently have to restate earnings increased increased by by nearly 20%. The likelihood likelihood of of being named in a federal federal class-action class-action lawsuit also increases, increases, and and the stock is likely to perform worse. The effect tended to be larger for larger firms. Although a correlation between them leaving and subsequent bad performance at the firm is suggestive, it does not mean that such directors are always jumping off a sinking ship. Often they “trade up.” L eaving riskier, smaller firms for larger and more stable firms.B ut the researchers believe that outside directors have an easier time of avoidinga blow to their reputations if they leave a firm before bad news breaks, even if a reviewof history shows they were on the board at the time any wrongdoing occurred. Firms whotough times may have to create incentives.through toughwant to keep their outside directors throughOtherwise outside directors will follow the example of Ms. Simmons, once again very popular on campus.21. According to Paragraph 1, Ms. Simmons was criticized for .[A]gaining excessive profits[B]failing to fulfill her duty[C]refusing to make compromises[D]leaving the board in tough times22. We learn from Paragraph 2 that outside directors are supposed to be .[A]generous investors[B]unbiased executives[C]share price forecasters[D]independent advisers23. According to the researchers from Ohio University after an outside director’ssurprise departure, the firm is likely to .[A]become more stable[B]report increased earnings[C]do less well in the stock market[D]perform worse in lawsuits24. It can be inferred from the last paragraph that outside directors .[A]may stay for the attractive offers from the firm[B]have often had records of wrongdoings in the firm[C]are accustomed to stress-free work in the firm[D]will decline incentives from the firm25. The author’s attitude toward the role of outside directors is .[A]permissive[B]positive[C]scornful[D]criticalText 2Whatever happened to the death of newspaper? A year ago the end seemed near. The recession threatened to remove the advertising and readers that had not already fled tothe internet. Newspapers like the San Francisco Chronicle were chronicling their own doom. America’s Federal Trade commission launched a round of talks about how to save newspapers. Should they become charitable corporations? Should the state subsidize them ? It will hold another meeting soon. But the discussions now seem out of date.In much of the world there is the sign of crisis. German and Brazilian papers have shrugged off the recession. Even American newspapers, which inhabit the most troubledcome of the global industry, have not only survived but often returned to profit. Not the 20% profit margins that were routine a few years ago, but profit all the same.It has not been much fun. Many papers stayed afloat by pushing journalists overboard. The American Society of News Editors reckons that 13,500 newsroom jobs have gone since 2007. Readers are paying more for slimmer products. Some papers even had the nerve to refuse delivery to distant suburbs. Yet these desperate measures measures have have have proved the proved the proved the right right ones and, sadly for many journalists, they can be pushed further.Newspapers Newspapers are are becoming more balanced balanced businesses, businesses, businesses, with with with a a healthier healthier mix mix of revenues from readers and advertisers. American papers have long been highly unusual in their reliance on ads. Fully 87% of their revenues came from advertising in 2008, according to the Organization for Economic Cooperation & Development (OECD). In Japan the proportion is 35%. Not surprisingly, Japanese newspapers are much more stable.The whirlwind that swept through newsrooms harmed everybody, but much of the damage has been concentrated in areas where newspaper are least distinctive. Car and film reviewers have gone. So have science and general business reporters. Foreign bureaus have been savagely cut off. Newspapers are less complete as a result. But completeness is no longer a virtue in the newspaper business.26. By saying “Newspapers like … their own doom ” (Lines 3-4, Para. 1), the authorindicates that newspaper .[A]neglected the sign of crisis[B]failed to get state subsidies[C]were not charitable corporations[D]were in a desperate situation27. Some newspapers refused delivery to distant suburbs probably because .[A]readers threatened to pay less[B]newspapers wanted to reduce costs[C]journalists reported little about these areas[D]subscribers complained about slimmer products28. Compared with their American counterparts, counterparts, Japanese Japanese newspapers newspapers are are much more stablebecause they .[A]have more sources of revenue[B]have more balanced newsrooms[C]are less dependent on advertising[D]are less affected by readership29. What can be inferred from the last paragraph about the current newspaper business?[A]Distinctiveness is an essential feature of newspapers.[B]Completeness is to blame for the failure of newspaper.[C]Foreign bureaus play a crucial role in the newspaper business.[D]Readers have lost their interest in car and film reviews.30. The most appropriate title for this text would be .[A]American Newspapers: Struggling for Survival[B]American Newspapers: Gone with the Wind[C]American Newspapers: A Thriving Business[D]American Newspapers: A Hopeless StoryText 3We tend to think of the decades immediately following World War II as a time of prosperity and growth, with soldiers returning home by the millions, going off to college on the G. I. Bill and lining up at the marriage bureaus.But when it came to their houses, it was a time of common sense and a belief that less could truly be more. During the Depression and the war, Americans had learned to live with less, and that restraint, in combination with the postwar confidence in the future, made small, efficient housing positively stylish.Economic condition was only a stimulus for the trend toward efficient living. The phrase “less is more ” was actually first popularized by a German, the architect Ludwig Mies van der Rohe, who like other people associated with the Bauhaus, a school of design, emigrated to the United States before World War IIand took up posts at American architecture schools. These designers came to exert enormous influence on the course of American architecture, but none more so that Mies.Mies ’s signature phrase means that less decoration, properly organized, has more impact that a lot. Elegance, he believed, did not derive from abundance. Like other modern architects, he employed metal, glass and laminated wood-materials that we take for granted today buy that in the 1940s symbolized the future. Mies ’s sophisticatedpresentation masked the fact that the spaces he designed were small and efficient, rather than big and often empty.T he he apartments in apartments in apartments in the elegant towers the elegant towers the elegant towers Mies built Mies built Mies built on Chicago on Chicago ’s Lake Shore Drive, for example, were smaller-two-bedroom units under 1,000 square feet-than those in their older neighbors along the city ’s Gold Coast. But they were popular because of their airy glass walls, the views they afforded and the elegance of the buildings ’ details and proportions, the architectural equivalent of the abstract art so popular at the time.The trend toward “less ” was not entirely foreign. In the 1930s Frank Lloyd Wright started building more modest and efficient houses-usually around 1,200 square feet-than the spreading two-story ones he had designed in the 1890s and the early 20th century.The “Case Study Houses ” commissioned commissioned from from talented modern architects by California Arts & Architecture Architecture magazine magazine between 1945 and 1962 were yet another homegrown influence on the “less is more ” trend. Aesthetic effect came from the landscape, new materials and forthright detailing. In his Case Study House, Ralph everyday life – few American families acquired helicopters, though most eventually got clothes dryers – but his belief that self-sufficiency was both desirable and inevitable was widely shared.31. The postwar American housing style largely reflected the Americans ’ .[A]prosperity and growth[B]efficiency and practicality[C]restraint and confidence[D]pride and faithfulness32. Which of the following can be inferred from Paragraph 3 about Bauhaus?[A]It was founded by Ludwig Mies van der Rohe.[B]Its designing concept was affected by World War II.[C]Most American architects used to be associated with it.[D]It had a great influence upon American architecture.33. Mies held that elegance of architectural design .[A]was related to large space[B]was identified with emptiness[C]was not reliant on abundant decoration[D]was not associated with efficiency34. What is true about the apartments Mies building Chicago’s Lake Shore Drive?[A]They ignored details and proportions.[B]They were built with materials popular at that time.[C]They were more spacious than neighboring buildings.[D]They shared some characteristics of abstract art.35. What can we learn about the design of the “Case Study House”?[A]Mechanical devices were widely used.[B]Natural scenes were taken into consideration[C]Details were sacrificed for the overall effect.[D]Eco-friendly materials were employed.Text 4Will the European Union make it? The question would have sounded strange not long ago. Now even the project’s greatest cheerleaders talk of a continent facing a “Bermuda triangle” of debt, population decline and lower growth.As well as those chronic problems, the EU face an acute crisis in its economic core, the 16 countries that use the single currency. Markets have lost faith that the euro zone’s economies, weaker or stronger, will one day converge thanks to the discipline of sharing a single currency, which denies uncompetitive members the quick fix of devaluation.Yet the debate about how to save Europe’s single currency from disintegration is stuck. It is stuck because the euro zone’s dominant powers, France and Germany, agree on the need for greater harmonization within the euro zone, but disagree about what to harmonies.Germany thinks the euro must be saved by stricter rules on borrow spending and competitiveness, barked by quasi-automatic sanctions for governments that do not obey.These might include threats to freeze EU funds for poorer regions and EU mega-projects and even the suspension of a country’s voting rights in EU ministerial councils. It insists that economic co-ordination should involve all 27 members of the EU club, among whom there is a small majority for free-market liberalism and economic rigour; in the inner core alone, Germany fears, a small majority favour French interference.A “southern” camp headed by French wants something different: ”European economic government” within an inner core of euro-zone members. Translated, that meanspoliticians intervening in monetary policy and a system of redistribution from richer to poorer members, via cheaper borrowing for governments through common Eurobonds or complete fiscal transfers. Finally, figures close to the France government have murmured, curo-zone members should agree to some fiscal and social harmonization: e.g., curbing competition in corporate-tax rates or labour costs.It is too soon to write off the EU. It remains the world’s largest trading block. At its best, the European project is remarkably liberal: built around a single market of 27 rich and poor countries, its internal borders are far more open to goods, capital and labour than any comparable trading area. It is an ambitious attempt to blunt thesharpest edges of globalization, and make capitalism benign.36. The EU is faced with so many problems that .[A] it has more or less lost faith in markets[B] even its supporters begin to feel concerned[C] some of its member countries plan to abandon euro[D] it intends to deny the possibility of devaluation37. The debate over the EU’s single currency is stuck because the dominantpowers .[A] are competing for the leading position[B] are busy handling their own crises[C] fail to reach an agreement on harmonization[D] disagree on the steps towards disintegration38. To solve the euro problem ,Germany proposed that .[A] EU funds for poor regions be increased[B] stricter regulations be imposed[C] only core members be involved in economic co-ordination[D] voting rights of the EU members be guaranteed39. The French proposal of handling the crisis implies that __ __.［［A］poor countries are more likely to get funds［B］strict monetary policy will be applied to poor countries［［C］loans will be readily available to rich countries［［D］rich countries will basically control Eurobonds40. Regarding the future of the EU, the author seems to feel __ __.［A］pessimistic［［［B］desperate［C］conceited［［D］hopefulPart BDirections:Read the following text and answer the questions by finding information from the right column that corresponds to each of the marked details given in the left column. There are two extra choices in the right column. Mark your answer on ANSWER SHEET 1. (10 points)4646．．Direction ：I n this section there is a text in English. T ranslate it into Chinese, write your translation on ANSWER SHEET 2. (15points)W ho would have thought that, globally, the IT industry produces about the same volumes of greenhouse gases as the world ’s airlines do-rough 2 percent of all CO2 emissions?M any any everyday everyday everyday tasks take tasks take tasks take a a a surprising toll on surprising toll on surprising toll on the the the environment. environment. A Google search Google search can can leak between 0.2 and 7.0 grams of CO2 depending on how many attempts are needed to get the “right ” answer. T o deliver results to its users quickly, then, Google has to maintain vast data centres round the world, packed with powerful computers. W hile producing large quantities of CO2, these computers emit a great deal of heat, so the centres need to be well air-conditioned, which uses even more energy.H owever, owever, Google Google and other other big big tech tech providers providers providers monitor monitor monitor their their their efficiency efficiency efficiency closely closely closely and and and make make improvements. Monitoring is the first step on the road to reduction, but there is much to be done, and not just by big companies.小作文参考答案【曲静老师版】Dear Li Ming, We are very happy to know that you have successfully passed the college entrance examination this year and have been admitted into Peking University. Allow us to give our most sincere congratulations on this exciting occasion. You have all along been working hard at your professional studies, and you are excellent in most subjects. Your success shows that only hard work can yield good results ，so I suggest that you should make a great progress in university life. We take this opportunity to express our best wishes to you. Wish you greater achievements in your college education. Yours sincerely, Zhang Wei 【马鹏老师版】Dear Ming, Congratulations! I am glad to hear that you have been admitted by MIT. Your efforts and commitment have been paid off. You are the honor of our family. Here come some my own advices of being a pre college student. First and foremost, you need to improve your communication because you will meet different people with different personalities in campus. Moreover, reading some reference books will help you to accumulate more knowledge and terms, which boost your competitiveness in campus. Once again congratulate for your achievement! Yours sincerely, Zhang Wei 大作文参考答案As is shown in the bar chart above, dramatic changes have taken place in the autos market shares within two years (from 2008 to 2009). The most obvious change was the market share of national brand, which had increased nearly by 10%, while Japan’s autos market share decreased roughly by 10%. The percentage of the US autos remained stable between 2008 and 2009. There are numerous reasons accounting for the phenomenon and I would like to explore a few of the most important ones here. Above all, as the development of technique and knowledge in native companies, a growing number of autos corporation developed many quality autos. Therefore, the national people changed the attitude to t he native brands and acknowledge them. What’ more, an overwhelming majority of people have been affected by the country patriotism ideology, partly owing to some actions of Japan triggering the emotion of people. Finally, Toyota brake error accidents signi significantly affects Japanese autos’ reputations and images. Safety concerns drove customers away ficantly affects Japanese autos’ reputations and images. Safety concerns drove customers away from Japanese products. Additionally, Fuel price drove consumers away from those American petrol digging and luxury autos. So it is not difficult to observe their steady performance. Based on what has been discussed above, we may reasonably conclude that the tendency described in graphic will continue for quite a long time. Hopefully, government could offer more friendly policies to China autos manufacturers to encourage quality improvement and technology innovation.完形填空参考答案1~5 ACBDD 6~10 BACCB 11~15 DBACA 16~20 ADACDTEXT 1 参考答案21．A。
测试技术基础课后习题答案
第2章习题及解答1.判断正误(1)凡频谱是离散的信号必然是周期信号。
( × )准周期信号(2)任何周期信号都由频率不同，但成整倍数比的离散的谐波叠加而成。
( × )(3)周期信号的频谱是离散的，非周期信号的频谱也是离散的。
( × )(4)周期单位脉冲序列的频谱仍为周期单位脉冲序列。
( √ )(5)非周期变化的信号就是随机信号。
( × )准周期信号(6)非周期信号的幅值谱表示的是其幅值谱密度与时间的函数关系。
( × )(7)信号在时域上波形有所变化，必然引起频谱的相应变化。
( × )(8)各态历经随机过程是平稳随机过程。
( √ )(9)平稳随机过程的时间平均统计特征等于该过程的集合平均统计特征。
( √ )(10)非周期信号的频谱都是连续的。
( × ) 准周期信号(11)单位脉冲信号的频谱是无限带宽谱（√）(12)直流信号的频谱是冲击谱（√）2.选择正确答案填空(1)描述周期信号的数学工具是(B )。
A.相关函数B. 傅里叶级数C. 拉普拉斯变换D. 傅里叶变换(2)描述非周期信号的数学工具是( C )。
A.三角函数B. 拉普拉斯变换C. 傅里叶变换D. 傅里叶级数(3)将时域信号进行时移，则频域信号将会( D )A.扩展B. 压缩C. 不变D. 仅有相移(4)瞬变信号的傅里叶变换的模的平方的意义为( C )A.信号的一个频率分量的能量B. 在f处的微笑频宽内，频率分量的能量与频宽之比C. 在f处单位频宽中所具有的功率(5)概率密度函数是在（C）域，相关函数是在（A）域，功率谱密度函数是在（D）域描述随机信号。
A.时间B. 空间C. 幅值D. 频率 (6) 白噪声信号的自相关函数是（C ）A.相关函数B. 奇函数C. 偶函数D. 不存在3．已知方波信号傅里叶级数，请描述式中各常数相的物理意义，并绘出频谱图。
见书中例题4．已知锯齿波信号傅里叶级数，请描述式中各常数相的物理意义，并绘出频谱图。
传感器(第四版) 课后习题答案(部分)
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3、电荷放大器的优点？电压放大器输出与电缆长度有关? 而电荷放大器输出与电缆长度无关？
（1）优点：压电元件自身电容和电缆寄生电容不影响电荷 放大器输出。
（2）电压放大器：
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分析：由电压的幅值计算公式可知，若作用在压电元件 上的为静态力（ω=0），则前置放大器的输入电压为零。 此时电荷会通过放大器的输入电阻和传感器本身的泄露电 阻漏掉。即压电式传感器不能用于静态物理量测量。
1测量测量电路前置级内屏蔽层芯线外屏蔽层传感器驱动电缆技术原理图?传感器与测量电路间的引线为双屏蔽层电缆其内屏蔽层与信号传输线即电缆芯线通过1
第四章 电容式传感器
1、改善单组式变极距型电容传感器非线性的方法： （1）可采用差动式结构，取两电容之差作为输出； （2）选择合适的测量电路，如运算放大器式电路。
《智能仪器》(第二版 程德福 林君)课后习题参考答案
智能仪器考试题型：名词解释、简答、简述、综合没有给重点，但是老师说考题都是由课后习题凝练出来的，所以我将大部分课后习题答案整理出来，仅供参考。
难免有错误，望大家谅解并指出。
课后习题参考第一章1-1 你在学习和生活中，接触、使用或了解了哪些仪器仪表？它们分别属于哪种类型？指出他们的共同之处与主要区别。
选择一种仪器，针对其存在的问题或不足，提出改进设想（课堂作业）。
解：就测量仪器而言，按测量各种物理量不同可划分为八种：几何量计量仪器、热工量计量仪器、机械量计量仪器、时间频率计量仪器、电磁计量仪器、无线电参数测量仪器、光学与声学测量仪器、电离辐射计量仪器。
1-2 结合你对智能仪器概念的理解，讨论“智能化”的层次。
解：P2 智能仪器是计算机技术和测量仪器相结合的产物，是含有微型计算机或微处理器的测量（或检测）仪器。
由于它拥有对数据的存储、运算、逻辑判断及自动化操作等功能，具有一定智能的作用（表现为智能的延伸或加强等），因而被称为智能仪器。
P5- P6 智能仪器的四个层次：聪敏仪器、初级智能仪器、模型化仪器和高级智能仪器。
聪敏仪器类是以电子、传感、测量技术为基础（也可能计算机技术和信号处理技术）。
特点是通过巧妙的设计而获得某一有特色的功能。
初级智能仪器除了应用电子、传感、测量技术外，主要特点是应用了计算机及信号处理技术，这类仪器已具有了拟人的记忆、存储、运算、判断、简单决策等功能。
模型化仪器是在初级智能仪器的基础上应用了建模技术和方法，这类仪器可对被测对象状态或行为作出评估，可以建立对环境、干扰、仪器参数变化作出自适应反映的数学模型，并对测量误差（静态或动态误差）进行补偿。
高级智能仪器是智能仪器的最高级别，这类仪器多运用模糊判断、容错技术、传感融合、人工智能、专家系统等技术。
有较强的自适应、自学习、自组织、自决策、自推理能力。
1-3 仪器仪表的重要性体现在哪些方面？P3-5解：（1）仪器及检测技术已经成为促进当代生产的主流环节，仪器整体发展水平是国家综合国力的重要标志之一（2）先进的科学仪器设备既是知识创新和技术创新的前提，也是创新研究的主题内容之一和创新成就得重要体现形式，科学仪器的创新是知识创新和及时创新的组成部分。
测控电路课后习题答案(全)
第一章绪论1-1为什么说在现代生产中提高产品质量与生产效率都离不开测量与控制技术？为了获得高质量的产品，必须要求机器按照给定的规程运行。
例如，为了加工出所需尺寸、形状的高精度零件，机床的刀架与主轴必须精确地按所要求的轨迹作相对运动。
为了炼出所需规格的钢材，除了严格按配方配料外，还必须严格控制炉温、送风、冶炼时间等运行规程。
为了做到这些，必须对机器的运行状态进行精确检测，当发现它偏离规定要求，或有偏离规定要求的倾向时，控制它，使它按规定的要求运行。
为了保证产品质量，除了对生产过程的检测与控制外，还必须对产品进行检测。
这一方面是为了把好产品质量关，另一方面也是为了检测机器与生产过程的模型是否准确，是否在按正确的模型对机器与生产过程进行控制，进一步完善对生产过程的控制。
生产效率一方面与机器的运行速度有关，另一方面取决于机器或生产系统的自动化程度。
为了使机器能在高速下可靠运行，必须要求机器本身的质量高，其控制系统性能优异。
要做到这两点，还是离不开测量与控制。
产品的质量离不开测量与控制，生产自动化同样一点也离不开测量与控制。
特别是当今时代的自动化已不是本世纪初主要靠凸轮、机械机构实现的刚性自动化，而是以电子、计算机技术为核心的柔性自动化、自适应控制与智能化。
越是柔性的系统就越需要检测。
没有检测，机器和生产系统就不可能按正确的规程自动运行。
自适应控制就是要使机器和系统能自动地去适应变化了的内外部环境与条件，按最佳的方案运行，这里首先需要的是对外部环境条件的检测，检测是控制的基础。
智能化是能在复杂的、变化的环境条件下自行决策的自动化，决策的基础是对内部因素和外部环境条件的掌握，它同样离不开检测。
1-2试从你熟悉的几个例子说明测量与控制技术在生产、生活与各种工作中的广泛应用。
为了加工出所需尺寸、形状的高精度零件，机床的刀架与主轴必须精确地按所要求的轨迹作相对运动。
为了炼出所需规格的钢材，除了严格按配方配料外，还必须严格控制炉温、送风、冶炼时间等运行规程。
2011信息安全数学基础习题答案
2011信息安全数学基础习题答案2011信息安全数学基础习题答案第⼀章整数的可除性1．证明：因为2|n 所以n=2k , k∈Z5|n 所以5|2k ，⼜（5，2）=1，所以5|k 即k=5 k1，k1∈Z7|n 所以7|2*5 k1 ,⼜（7，10）=1，所以7| k1即k1=7 k2，k2∈Z所以n=2*5*7 k2即n=70 k2, k2∈Z因此70|n2．证明：因为a3-a=(a-1)a(a+1)当a=3k，k∈Z 3|a 则3|a3-a当a=3k-1，k∈Z 3|a+1 则3|a3-a当a=3k+1，k∈Z 3|a-1 则3|a3-a所以a3-a能被3整除。
3．证明：任意奇整数可表⽰为2 k0+1，k0∈Z（2 k0+1）2＝4 k02+4 k0+1=4 k0 (k0+1)+1由于k0与k0+1为两连续整数，必有⼀个为偶数，所以k0 (k0+1)=2k所以（2 k0+1）2=8k+1 得证。
4．证明：设三个连续整数为a-1,a,a+1 则(a-1)a(a+1)= a3-a由第⼆题结论3|（a3-a）即3|(a-1)a(a+1)⼜三个连续整数中必有⾄少⼀个为偶数，则2|(a-1)a(a+1)⼜（3，2）=1 所以6|(a-1)a(a+1) 得证。
5．证明：构造下列k个连续正整数列：(k+1)！+2, (k+1)！+3, (k+1)！+4,……, (k+1)！+(k+1), k∈Z对数列中任⼀数 (k+1)！+i=i[(k+1)k…(i+1)(i-1)…2*1+1], i=2,3,4,…(k+1)所以i|(k+1)！+i 即(k+1)！+i为合数所以此k个连续正整数都是合数。
6．证明：因为1911/2＜14 ,⼩于14的素数有2，3，5，7，11，13经验算都不能整除191 所以191为素数。
因为5471/2＜24 ,⼩于24的素数有2，3，5，7，11，13，17，19，23经验算都不能整除547 所以547为素数。
自动检测技术及应用课后习题答案
第二版检测技术的选择题（上）2011年01月06日星期四 14:57第一部分思考题与习题答案1.单项选择题1）某压力仪表厂生产的压力表满度相对误差均控制在0.4%~0.6%，该压力表的精度等级应定为 C 级，另一家仪器厂需要购买压力表，希望压力表的满度相对误差小于0.9%，应购买 B 级的压力表。
A. 0 .2B. 0 .5C. 1 .0D. 1.52）某采购员分别在三家商店购买100kg大米、10kg苹果、1kg巧克力，发现均缺少约0.5kg，但该采购员对卖巧克力的商店意见最大，在这个例子中，产生此心理作用的主要因素是 B 。
A.绝对误差B.示值相对误差C.满度相对误差D.精度等级3）在选购线性仪表时，必须在同一系列的仪表中选择适当的量程。
这时必须考虑到应尽量使选购的仪表量程为欲测量的 C 左右为宜。
A.3倍B.10倍C.1.5倍D.0.75倍4）用万用表交流电压档(频率上限仅为5kHz)测量频率高达500kHz、10V左右的高频电压，发现示值还不到2V，该误差属于 D 。
用该表直流电压档测量5号干电池电压，发现每次示值均为1.8V，该误差属于 A 。
A.系统误差B.粗大误差C.随机误差D.动态误差5）重要场合使用的元器件或仪表，购入后需进行高、低温循环老化试验，其目的是为了 D 。
A.提高精度B.加速其衰老C.测试其各项性能指标D.提高可靠性2.各举出两个非电量电测的例子来说明1）静态测量； 2）动态测量；3）直接测量； 4）间接测量；5）接触式测量； 6）非接触式测量；7）在线测量； 8）离线测量。
3.有一温度计，它的测量范围为0～200℃，精度为0.5级，试求：1）该表可能出现的最大绝对误差为 A 。
A. 1℃B. 0.5℃C. 10℃D. 200℃2）当示值为20℃时的示值相对误差为 B ，100℃时的示值相对误差为 C 。
A. 1℃B. 5％C. 1％D. 10％4.欲测240V左右的电压，要求测量示值相对误差的绝对值不大于0.6%，问：若选用量程为250V电压表，其精度应选 B 级。
传感器与测试技术李晓莹高教版课后答案
《传感器与测试技术》课后习题答案第二章 信号分析与处理1-2、求解正弦信号wt x t x sin )(0=的绝对均值||x μ和均方根值x rms 。
1-3、求解指数函数at Ae t x -=)((a>0,t>0)的频谱。
1-4、求解被截断的余弦函数t w 0cos 的傅利叶变换。
⎩⎨⎧≥<=Tt Tt t t x ||0||cos )(0ω0 -TT1-1x(t)tωππωμ2;2sin 1)(lim 0000====⎰⎰∞→T x tdt x T dt t x TT T x 式中：()2sin 1)(10020020x dt t x T dt t x T x T T rms ===⎰⎰ωfj Adt e Ae dt et x f X ft j t ftj παπαπ2)()(022+=⋅==⎰⎰∞+--∞+∞--()[]210000222202sin sin 2)(2)(sin 2)(2)(sin 212cos )()(00θθππππππππππ⋅+⋅=⎥⎦⎤⎢⎣⎡--+++=+===--+-+--+∞∞--⎰⎰⎰c c T T f f T f f T f f T f f T dt e e e dtte f dt et x f X ft j t f j t f j TT TTft j ftj1-5、求解指数衰减振荡信号t w e t x at 0sin )(-=的频谱。
1-6、设有一时间函数f(t)及其频谱如图所示，求解信号t w t f 0cos )(的频谱，并画出频谱图。
又问：若m ωω<0时其频谱将会出现什么情况？当ω0<ωm 时，将会出现频率混叠现象第四章 测试系统的特性分析4-1、进行某动态压力测量时，所采用的压电式力传感器的灵敏度为-w mw mF(w)wf(t)t()()⎪⎪⎭⎫ ⎝⎛-+-++=-⋅===-∞+---+∞-+∞∞--⎰⎰⎰)(21)(21222sin )()(002022200200f f j f f j j dte e e j e dtet f edt et x f X ft j t f j t f j t ftj tftj παπαππππαπαπ[]())22(21)22(2121)(2cos )()()(0022220200f f F f f F dt e e e t f dte tf t f dt e t x f X ft j t f j t f j ft j ft j ππππππππππ-++=⋅⎥⎦⎤⎢⎣⎡+=⋅==-∞+∞---+∞∞-+∞∞--⎰⎰⎰90.9nC/MPa 。
2011年9月浙江省通用技术高考试题及答案
机密★考试结束前2011年9月普通高等学校招生浙江省统一考试通用技术试题本试题卷分第Ⅰ卷和第Ⅱ卷两部分。
全卷共8页，第Ⅰ卷1至5页，第Ⅱ卷6至8页。
满100分，考试时间90分钟。
请考生按规定用笔将所有试题的答案涂、写在答题纸上。
第Ⅰ卷（共40分）注意事项：1.答第Ⅰ卷前，考生务必将自己的姓名、准考证号用黑色字迹的签字笔或钢笔填写在卷题纸上。
2、每小题选出答案后，用2B铅笔把答题纸上对应题目的答案标号涂黑，如需改动，用橡皮擦干净后，再选涂其他答案标号。
不能答在试题卷上。
一、选择题（本大题20小题，每小题2分，共40分。
在每小题给出的四个选项中，只有一个是符合题目要求的）1．某公司开发的生物燃料新技术，通过光合作用将转基因单细胞植物转变成为乙醇和生物柴油等燃料，可用于驱动汽车等，减少石油资源的消耗。
下列关于该技术的说法种不恰当．．．的是 A．该技术符合设计的可持续发展原则B.该技术促进了生物技术的创新与发展C．该技术拓展了新能源的开发与利用D.该技术可以让人类不再担忧能源枯竭2．如图所示为人体下肢尺寸。
如果要制作椅子，在确定椅子座面的高度时，需要考虑的尺寸是A．L1B．L2C．L3D．L4．3．某学校兴趣小组同学设计一款楼道夜间自动照明装置，在设计中可以不考虑的因素是A．传感器的类型 B．照明装置的安装人员C．环境的干扰因索 D．照明的延迟时间4．如图所示是一款泡茶用的小茶具，它可以便捷地卡在茶杯的杯沿上，不会让茶叶散在杯中，也可以方便地架放在桌面上。
该小茶具的设计主要体现了设计的 A ．实用原则、创新原则 B ．经济原则、技术规范原则 C ．美观原则、经济原则 D ．道德原则、可持续发展原则5．李林通过通用技术的学习，提出了一些保温杯性能试验方案。
下列试验方案中不合理．．．的是 A ．保温试验：将开水倒入保温杯内，测量温度，旋紧杯盖，2小时后再测量水的温度 B ．渗漏试验：往杯中加水后，旋紧杯盖，把保温杯横放在桌面上，观察是否有水渗漏 C ．内胆异味试验：旋紧杯盖一段时间后打开杯盖，用鼻子感受内胆的气味 D ．跌落试验：用铁锤敲击保温杯，观察保温杯是否损坏6．推销员在推销某款复读机时说：“该产品具有跟读、复读、同步显示课文内容等功能；配备高保真耳机，可以欣赏立体声音乐；操作简便，携带方便，价格低，适合中学生使用。
微机原理课后习题参考答案_2011_简版
5． 设机器字长为 8 位。根据给出的不同形式的机器数，如下表，计算其对应的十进制表示的真值。 答： 二进制机器数 01101 1110 0101 1001 1000 1101 1111 1001 （若为）无符号数 110 89 141 249 （若为） 原码 110 89 -13 -121 （若为）反码 110 89 -114 -6 （若为）补码 110 89 -115 -7
第一章 一．思考题（略） 二．综合题 1． 设机器字长为 8 位，写出下列用真值表示的二进制数的原码、补码和反码。答： 真值 （1）+0010101B （2）+1110001B （3）+1010011B （4）-0010101B （5）-1111011B （6）-1001010B 原码 00010101 01110001 01010011 10010101 11111011 11001010 反码 00010101 01110001 01010011 11101010 10000100 10110101 补码 00010101 01110001 01010011 11101011 10000101 10110110
5CH 00H 7AH 53H 42H FFH 12H 00H 5BH 0AH
20A28H 20A29H H 20A2AH 20A2BH H 20A2CH 20A2DH H 20A2EH 20A2FH H 20A30H
堆栈必须为字操作
ห้องสมุดไป่ตู้
20A31H （） H （2）SS=20A0H， SP=0028H 7． 若某存储单元的实际地址为 2BC60H，且该存储单元所在的段首地址为 2AF00H，则该存储单 元在段内的偏移地址为多少？答： 偏移地址=2BC60H-2AF00H=0D60H
传感器期末试卷A答案
上海中华职业技术学院20 10 ～20 11学年第 二 学期2009 级 电气自动化 专业 编号＿＿＿传感器原理及应用 课程 期末 考试试卷 [A 卷]答案考试形式说明：笔试开卷，允许带教材及笔记考试时间：90分钟一、 填空题：（每空1分，共计20分）1、热电偶用于感温的一端称为 热 (热,冷)端,自由端是指 冷 端。
2、光敏电阻受光照时的电阻变 小(大,小),其响应较 慢 (快,慢)。
3、金属热电阻的电阻值随着温度的升高而 增大 ，一般表征为 正 （正、负）温度特性。
4、电容式传感器主要分为三类，分别为： 变介电常数型 、 变面积型 和 变间距型 。
5、检测方法按照被测量是否随时间变化分类分为： 静态测量 和 动态测量 。
6、超声波的发生基于 逆压电 效应，超声波的接收基于 正压电 效应。
7、一般传感器由三部分组成，分别为 敏感元件 、 转换元件 、 基本转换电路 。
8、目前国际上常用的温标有 摄氏温标 、 华氏温标 、 热力学温标、 国际实用温标 。
二、选择题（每题2分，共计30分）1、 湿敏电阻的输出电阻值随着湿度的增加而 B 。
A 、增大 B 、减少 C 、不变 D 、不定2、测得某检测仪表的输入信号中,有用信号为20毫伏,干扰电压也为20毫伏, 则此时的信噪比为 C 。
A 、20dB B 、1 dB C 、0 dB3、下列传感器不能用来测位移的是 C 。
A 、电阻式传感器B 、电容式传感器C 、压电式传感器D 、电感式传感器4、 如图所示，R1为固定电阻，R2为负温度系数的热敏电阻，L 为小灯泡，当温度降低时：CA 、R1两端的电压增大B 、电流表的示数增大C 、小灯泡的亮度变强D 、小灯泡的亮度变弱5、 用摇控器调换电视机频道的过程，实际上就是传感器把光信号转换成电信号的过程．下列属于这类传感器的是 AA 、红外报警装置B 、走廊照明灯的声控开关C、自动洗衣机中的压力传感装置D、电饭煲中控制加热和保温的温控器6、传感器的输出量通常为 BA 非电量信号B 电量信号C 位移信号D 光信号7、人造卫星的光电池板利用了 A 。
微机原理课后习题参考答案_2011_简版
习题答案1－6 将下列十进制数转换为二进制数、十六进制数和BCD 数 （1）124．625 （6）268．875 解：（1）124＝01111100B ＝7CH ，0.625×16＝10，所以0.625＝0.AH=0.1010B ∴124.625=7C.AH=01111100.1010B=000100100100.011000100101BCD（2）268＝256＋12＝100001100B ＝10CH ，0.875×16＝14，∴0.875＝0.EH=0.1110B. ∴268.875=10C.EH=100001100.111B=001001101000.100001110101BCD 1－7 用16位二进制数表示出下列十进制数的原码、反码和补码。
（1）＋128 （4）－5 解：（1）+128 的原码和补码反码均为0000000100000000B（4）－5的原码为1000000000000101B ，反码为1111111111111010B ，补码为1111111111111011B 。
1－10 试绘出以下十六进制数在内存中存放的示意图。
设存放地址均为00H 。
解：（1）F7H （2）03BAH （3）C804326BH （4）1122334455667788H2－1 请将左边的术语和右边的含义联系起来，在括号中填入你选择的代号字母： 1. 字长 （i ）a. 指由8个二进制位组成的通用基本单元。
2. 字节 （a ）b. 是CPU 执行指令的时间刻度。
3. 指令 （h ）c. μPS 所能访问的存储单元数，与CPU 地址总线条数有关。
4. 基本指令执行周期（g ）d. 唯一能代表存储空间每个字节单元的地址，用5位十六进制数表示。
5. 指令执行时间 （j ）e. CPU 访问1次存储器或I/O 操作所花的时间。
6. 时钟周期 （b ）f. 由段基址和偏移地址两部分组成，均用4位十六进制数表示。
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传感器与检测技术思考题参考答案第一章1. 传感器由那几部分组成？并说明各组成部分的功能。
答:传感器一般由敏感元件、转换元件、转换电路等几部分组成。
敏感元件：它是直接感受被测量，并输出与被测量成确定关系的某一物理量的元件。
转换元件：敏感元件的输出就是它的输入，它把输入转换成电路参数。
转换电路：将转换元转换成的电路参数接入转换电路，便可转换成电量输出。
2. 什么是传感器动态特性和静态特性，简述在什么条件下只研究静态特性就能够满足通常的需要，而在什么条件下一般要研究传感器的动态特性？在时域条件下研究静态，在频域条件下研究动态 3. 请使用性能指标描述检测系统的静态特性。
（P9-P11）4. 某线性位移测量仪，当被测位移由4.5mm 变到5.0mm 时，位移测量仪的输出电压由3.5V 减至2.5V ，求该仪器的灵敏度。
解：该仪器的灵敏度为25.40.55.35.2-=--=S mV/mm5. 某测温系统由以下四个环节组成，各自的灵敏度如下：铂电阻温度传感器： 0.45Ω/℃ 电桥： 0.02V/Ω放大器： 100(放大倍数) 笔式记录仪： 0.2cm/V 求：(1)测温系统的总灵敏度；(2)记录仪笔尖位移4cm 时，所对应的温度变化值。
解：（1）测温系统的总灵敏度为18.02.010002.045.0=⨯⨯⨯=S cm/℃（2）记录仪笔尖位移4cm 时，所对应的温度变化值为22.2218.04==t ℃ 第二章 检测系统的误差合成1.什么是系统误差？产生系统误差的原因是什么？如何发现系统误差？减少系统误差有哪几种方法？答：系统误差是指在相同的条件下，多次重复测量同一量时，误差的大小和符号保持不变，或按照一定的规律变化的误差。
…2.服从正态分布规律的随机误差有哪些特性?答：服从正态分布规律的随机误差的特性有：对称性 随机误差可正可负，但绝对值相等的正、负误差出现的机会相等。
也就是说f (δ)- δ曲线对称于纵轴。
有界性 在一定测量条件下，随机误差的绝对值不会超过一定的范围，即绝对值很大的随机误差几乎不出现。
抵偿性 在相同条件下，当测量次数n →∞时，全体随机误差的代数和等于零，即0lim1=∑=∞→ni in δ。
单峰性 绝对值小的随机误差比绝对值大的随机误差出现的机会多，即前者比后者的概率密度大，在δ=0处随机误差概率密度有最大值。
3. 等精度测量某电阻10次，得到的测量列如下：R 1＝167.95Ω R 2＝167.45Ω R 3＝167.60Ω R 4＝167.60Ω R 5＝167.87Ω R 6＝167.88Ω R 7＝168.00Ω R 8＝167.850Ω R 9＝167.82Ω R 10＝167.61Ω (1)求10次测量的算术平均值R ，测量的标准偏差σ 和算术平均值的标准误差r σ。
(2)若置信概率取99.7％，写出被测电阻的真值和极限值。
解：(1)求10次测量的算术平均值R ，测量的标准误差σˆ和算术平均值的标准误差r σˆ。
Ω=+++++++++=++=∑=763.1671061.16782.16785.16700.16888.16787.16760.16760.16745.16795.1671010121i nR R R R Ω=++++++⨯++==-=--=∑∑∑===1824.0)153.0057.0087.0237.0108.0107.0163.02313.0187.0(919111)(11ˆ22222222210121212i i n i i ni i v v n x x n σr σˆ=Ω==0577.0101824.0nσ(2)若置信概率取99.7％，被测电阻的真值为：Ω±=⨯±=)173.0763.167(3763.1670r R σ极限值为：Ω±=±=)547.0763.167(3763.167σm R3.1 电阻式传感器1.金属电阻应变片与半导体材料的电阻应变效应有什么不同? 答：金属电阻的应变效应主要是由于其几何形状的变化而产生的，半导体材料的应变效应则主要取决于材料的电阻率随应变所引起的变化产生的。
2．如将两个100Ω电阻应变片平等地粘贴在钢制试件上，试件截面积为0.5×10-4m 2，弹性模量E=200GN/m 2，由50kN 的拉力所引起的应变片电阻变化为1Ω。
把它们接入交流电桥中，电桥电源电压为1V ，求应变片灵敏系数和电桥输出电压。
解：因为应变应力=E 所以005.0)10200()105.0(5000094=⨯⨯⨯===-SE F E 应力ε 故应变片的灵敏系数k 为2005.01001=⨯=∆=εR R k 当电阻应变片与匹配电阻构成全等臂交流电桥时，两应变片处于不同的桥臂时将会有不同的输出：（1） 两应变片接在相邻的桥臂时，由于两应变片平等贴在试件上，两电阻变化值均为1Ω，且符号相同，故它们对电桥的作用相互抵消，输出电压为零。
这种效果在应变片温度补偿中得到了应用。
（2） 两应变片接在相对的桥臂时，因此时它们对电桥的贡献相当于两个单臂电桥，故其输出电压为mV 5V 005.0110012121==⨯⨯=∆=U R R U O 应当指出：如果把两应变征平等粘贴在水平放置的悬臂梁的上、下两侧，并把它们接入相邻臂，则组成了差动电桥，输出电压U O 也将是5mV ，因为那时两应变片的电阻变化值的符号相反。
3.如图所示电路是电阻应变仪中所用的不平衡电桥的简化电路，图中R2=R3=R 是固定电阻，R1与R4是电阻应变片，工作时R1受拉，R4受压，ΔR=0，桥路处于平衡状态，当应变片受力发生应变时，桥路失去平衡，这时，就用桥路输出电压Ucd 表示应变片变后电阻值的变化量。
试证明：Ucd=-（E/2）(ΔR/R)。
Eacd证：R R R R R R ∆-=∆+=41, =-=ad ac cd U U U E R R RR E R R R R E R R R R 2242∆-∆-=+∆--+∆+略去R ∆的第二项，即可得RRE U cd ∆⋅-=23.2 电容式传感器4.有一只变极距电容传感元件，两极板间有效面积为8×10-4m 2，两极板间的距离为1mm ，已知空气的相对介电常数为1.0006，试计算该传感器的位移灵敏度。
解：求变极距型电容传感元件的位移灵敏度时只要将公式δεε/0S C r =对δ求导即可， 即此传感器的位移灵敏度为：mnF m F S d dC r /7/1070)101(1080006.11085.8102341220-=⨯-=⨯⨯⨯⨯⨯-=-=----δεεδ 式中负号表示当极距增大时，电容值减小.5.变极距电容传感器的测量电路为运算放大器电路，如图所示。
C 0=200pF ，传感器的起始电容量C x0=20pF ,定动极板距离d 0=1.5mm ,运算放大器为理想放大器(即K →∞,Z i →∞),R f 极大,输入电压u 1=5sinωt V 。
求当电容传感动极板上输入一位移量△x =0.15mm 使d 0减小时,电路输出电压u 0为多少? 解：由测量电路可得ϖϖsin 45sin 515.05.15.120200000000=⨯-⨯=∆--=-=t u xd d C C u C C u i x i x /V3.3 电感式传感器6. 如图所示的差动电感式传感器的桥式测量电路，L 1、L 2为传感器的两差动电感线圈的电感，其初始值均为L 0。
R 1、R 2为标准电阻，u 为电源电压。
试写出输出电压u 0与传感器电感变化量△L 间的关系。
题6图解：输出与输入的关系是u R L L f L L f R L L f L L f u ⎪⎪⎭⎫⎝⎛+∆-∆--+∆+∆+=22200212000)](2[)(2)](2[)(2ππππ 若电感增量无穷小，且两个电阻均为R ，则：u RfL L f u 2200)2(4+∆=ππ7.如图所示为一差动整流电路，试分析电路的工作原理。
题7图答：这是简单的电压输出型，动铁芯移动时引起上下两个全波整流电路输出差动电压，中间可调整零位，输出电压与铁芯位移成正比。
这种电路由二极管的非线性影响以及二极管正向饱和压降和反向漏电流的不利影响较大。
3.4 电涡流式传感器8.电涡流式传感器的灵敏度主要受哪些因素影响？它的主要优点是什么？答：电涡流式传感器的灵敏度主要受导体的电导率、磁导率、几何形状，线圈的几何参数，激励电流频率以及线圈到被测导体间的距离等因素影响。
电涡流式传感结构简单、频率响应宽、灵敏度高、测量范围大、抗干忧能力强，特别是有非接触测量的优点，因此在工业生产和科学技术的各个领域中得到了广泛的应用。
3.5 压电式传感器9.用压电式传感器能测量静态或变化很缓慢的信号吗？为什么？答：(1)由于不可避免地存在电荷泄漏，利用压电式传感器测量静态或准静态量值时，必须采取一定措施，使电荷从压电元件经测量电路的漏失减小到足够小的程度；(2)而在作动态测量时，电荷可以不断补充，从而供给测量电路一定的电流，故压电式传感器适宜作动态测量。
10.压电式传感器的前置放大器的作用是什么？电压式与电荷式前置放大器各有何特点？ 答：压电式传感器的前置放大器的作用是：(1)放大压电式传感器输出的弱信号;(2)把压电式传感器的高输出阻变换成低阻抗输出。
电压放大器：其输出电压与输入电压（传感器的输出电压）成正比；电荷放大器：其输出电压与输入电荷成正比，输出电压几乎不受联接电缆长度变化的影响，这是电荷放大器的最大优点。
11．压电式传感器测量电路的作用是什么?其核心是解决什么问题? 答：压电式传感器测量电路的作用是将压电晶体产生的电荷转换为电压信号输出，其核心是要解决微弱信号的转换与放大，得到足够强的输出信号。
3.5 热电式传感器12. 什么是金属导体的热电效应?试说明热电偶的测温原理。
答：热电效应就是两种不同的导体或半导体A 和B 组成一个回路，其两端相互连接时，只要两结点处的温度不同，回路中就会产生一个电动势，该电动势的方向和大小与导体的材料及两接点的温度有关。
热电偶测温就是利用这种热电效应进行的，将热电偶的热端插入被测物，冷端接进仪表，就能测量温度。
13.试述热电偶冷端温度补偿的几种主要方法和补偿原理。
答：热电偶冷端温度补偿的方法主要有：一是冷端恒温法。
这种方法将热电偶的冷端放在恒温场合，有0℃恒温器和其他恒温器两种；二是补偿导线法。
将热电偶的冷端延伸到温度恒定的场所(如仪表室)，其实质是相当于将热电极延长。
根据中间温度定律，只要热电偶和补偿导线的二个接点温度一致，是不会影响热电动势输出的；三是计算修正法。
修正公式为：)t ,(t E )t (t,E )t (t,E 01AB 1AB 0AB +=；四是电桥补偿法。