电子科技大学2018年泛函分析考博考博试题及答案

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2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:20

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:20

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题Do you have any()about what living beings on other planets would be like?问题1选项A.idealprehensionC.notionD.intelligence【答案】C【解析】句意:你对生活在其他星球上的生物的样子有什么概念吗?考查名词辨析。

ideal 理想,典范;comprehension理解,领悟能力; notion概念,想法;intelligence 智力,情报,聪颖。

因此C符合句意。

2.单选题Mrs. Deborah could not help exclaiming against the()of her master, and especially against his suffering her to conceal the father of the child.问题1选项A.biasB.clemencydnessD.justice 【答案】B【解析】句意: Deborah夫人忍不住指责丈夫的宽容,特别是允许她对孩子父亲隐瞒的做法。

考查名词辨析。

bias 偏见,偏爱;clemency 仁慈,温和,宽容,宽厚; mildness 温和,温暖;justice 司法,法律制裁,正义,法官。

根据后半句句意可知B符合句意。

3.单选题The device can()different measurements by electronics means.问题1选项A.imitateB.copyC.mockD.fake【答案】A【解析】句意:这个设备能通过电子手段来模拟不同的尺寸。

考查动词辨析。

Imitate模仿,仿效,模仿(某人的讲话、举止); copy 复制,抄袭;mock 愚弄,嘲弄;fake 捏造,假装…的样子。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:45

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:45

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题()dull he may be, he is certainly a very successful top executive.问题1选项A.AlthoughB.WhateverC.AsD.However【答案】D【解析】句意:不管他多么无趣,但是他确实是一位非常成功的高级管理人员。

考查连词辨析。

although 尽管,虽然,然而(其后跟正常语序的句子);whatever 无论什么;as 因为,随着,虽然(引导让步状语从句时,该从句中的表语成分一般放在句首),当…时;however 不管怎样(接副词或形容词)。

由句意可知前后为让步关系。

故选D。

2.单选题Please()yourself from smoking and spitting in public places, since the law forbids them. 问题1选项A.restrainB.hinderC.restrictD.prohibit 【答案】A【解析】句意:请不要在公共场所吸烟以及随地吐痰!这可是违法的!考查动词辨析。

restrain制止,阻止,管制,忍住,后可接反身代词和from,构成restrain oneself from...表示戒掉…习惯,符合题意。

hinder 妨碍,阻止,后不接from,故排除。

restrict 限制,后接介词 to,构成restrict to表示仅限于……,不符合句意,故排除。

prohibit 禁止,可以直接接宾语,后面不接from,也排除。

因此选A。

3.单选题The boy cycling in the street was knocked down by a minibus and received()injuries.问题1选项A.fatalB.excessiveC.disastrousD.exaggerated【答案】A【解析】句意:在街上,骑车的男孩被一辆小型客车撞倒,生命垂危。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:86

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:86

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题The machine might work if we()it very carefully.问题1选项A.obtainB.operateC.opposeD.object【答案】B【解析】句意:如果我们非常小心地操作这台机器,那么它可能会运转。

考查动词辨析。

obtain (尤指经努力)获得,赢得,存在;operate 运转,工作,操作,控制,使运行;oppose 反对,对抗;object 反对,拒绝。

空格处动词的宾语为it,即指代前面的machine(机器),因此B符合句意。

2.单选题It takes much time to solve the problem one by one. Can we generalize common()to apply to similar problems?问题1选项A.meansB.techniquesC.tipsD.solutions 【答案】D【解析】句意:一个接一个地解决问题需要很多吋间。

我们能归纳出适用于所有类似问题的通用解决方法吗?考查名词辨析。

means 手段,方法;technique 技巧,技艺,工艺;tip尖端,尖儿,端;solution 解决方案,溶液,溶解。

根据关键信息“problem (问题)”可知D符合句意。

3.单选题Those who()traffic regulations should be punished.问题1选项A.rotateB.violateC.abuseD.degrade【答案】B【解析】句意:违反交通法规的那些人应该受处罚。

考查动词辨析。

rotate (使)旋转,转动;(工作)由…轮值;violate 违反,违犯,违背(法律、协议等),侵犯(隐私等);abuse 滥用,虐待;degrade 贬低,使……丢脸,使……降级,使降解。

电子科大2017考博泛函分析真题及答案

电子科大2017考博泛函分析真题及答案

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2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:42

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:42

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题The device can()different measurements by electronics means.问题1选项A.imitateB.copyC.mockD.fake【答案】A【解析】句意:这个设备能通过电子手段来模拟不同的尺寸。

考查动词辨析。

Imitate模仿,仿效,模仿(某人的讲话、举止); copy 复制,抄袭;mock 愚弄,嘲弄;fake 捏造,假装…的样子。

故A符合句意。

2.单选题Fewer and fewer of today’s workers expect to spend their working lives in the same field,()the same company.问题1选项A.all elseB.much worseC.let aloneD.less likely 【答案】C【解析】句意:如今越来越少的工人期望在工作生涯中都一直在同样的领域工作,更不必说一直在同样的公司工作。

考查短语辨析。

all else 其他所有;much worse 更糟糕的是;let alone 更不用说,听任,不打扰;less likely 最不可能的是,较少可能。

空格前后表示递进,故选C。

3.单选题Do you regret paying fifty dollars for the dog?” “No, I would gladly pay()for hi m.”问题1选项A.as much twiceB.twice so muchC.much twiceD.twice as much【答案】D【解析】句意:你后悔为这条狗支付50美元不?”。

“不,我乐意为了他支付双倍”。

语法题。

考查倍数的表达。

倍数的固定表达方式: 倍数+as+形容词或副词+(as+另一比较对象),前文己交代另一比较对象的情况下,括号中的部分可省略来避免重复,因此D正确。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:64

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:64

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题It is an offence to show()against people of different races.问题1选项A.distinctionB.differenceC.separationD.discrimination【答案】D【解析】句意:对不同种族的人表现出歧视是一种冒犯。

考查名词辨析。

distinction区别,特性;difference差异,不同;separation分离,距离;discrimination 歧视,区别,辨别。

故D符合句意。

2.单选题We()managed to have people accept our theory after a long, hard struggle.问题1选项A.momentarilyB.suddenlyC.graciouslyD.gradually 【答案】D【解析】句意:经过长期的艰苦努力之后,我们逐渐让他们接了受我们的理论。

考查副词辨析。

momentarily 顷刻之间,马上;suddenly意外地,忽然地;graciously优雅地,慈样地;gradually逐步地,渐渐地。

根据后文的after a long, hard struggle (长期的艰苦努力之后)可知D正确。

3.单选题Fertilizer, natural substance or mixture is used to()soil so as to promote plant growth. 问题1选项A.enactB.enlargeC.encloseD.enrich【答案】D【解析】句意:肥料、自然物质或混合物被用来使土地肥沃,以促进植物生长。

考查动词辨析。

Enact 通过(法律),扮演,担任…角色; enlarge扩大,扩充,扩展; enclose围绕,放入封套; enrich使充实,使肥沃,使富足。

2005年秋电子科技大学考博英语真题及详解【圣才出品】

2005年秋电子科技大学考博英语真题及详解【圣才出品】

2005年秋电子科技大学考博英语真题及详解I.Vocabulary(0.5×30)Directions:In each item of the following,choose one from A,B,C,or D that best keeps the meaning of the sentence if it is substituted for the underlined word(s).Mark your choice on the ANSWER SHEET with a pencil.1.In easy times we are ambivalent—the leader,after all,makes demands,challenges the status quo,shakes things up.A.vague;carries out reformsB.uncertain;effects radical changesC.hesitant;establishes authorityD.indifferent;puts things in good order【答案】B【解析】ambivalent矛盾的,好恶相克的;shake things up指彻底改变形势。

所以选项B 中uncertain,effects radical changes分别与之对应。

2.Greet leaders are almost always great simplifiers,who cut through argument,debate and doubt to offer a solution everybody can understand and remember.A.do away withB.bring to an endC.sum upD.resolve【答案】B【解析】cut through穿过;克服,避开;不理睬,剪断;这里指“避免争论和怀疑”。

计算机考博英语试题及答案

计算机考博英语试题及答案

计算机考博英语试题及答案Introduction:In the field of computer science, obtaining a doctoral degree is a significant achievement. To attain this goal, candidates are required to pass an examination that tests their knowledge in various areas. Among these, the English language proficiency is essential for researchers to communicate effectively and contribute to the global scientific community. In this article, we will provide a sample of computer-based examination questions for the English section, along with the corresponding answers to help candidates prepare for the exam.Section 1: Reading ComprehensionInstructions: Read the following passage and answer the questions that follow.[Passage]Question 1: According to the passage, what is the purpose of the computer-based examination?Answer: The computer-based examination aims to assess the English language proficiency of candidates pursuing a doctoral degree in computer science.Question 2: What is one benefit mentioned in the passage of passing the examination?Answer: Passing the examination demonstrates an ability to communicate effectively with other researchers in the global scientific community.Question 3: What skills or abilities are required to succeed in the examination?Answer: Candidates are required to have a strong understanding of the English language, including reading comprehension, vocabulary, and grammar.Section 2: Vocabulary and GrammarInstructions: Choose the correct word or phrase to complete each sentence.Question 1: The researchers conducted a _______ investigation to gather data for their study.a) thoroughb) throughc) thoughQuestion 2: _______ the challenging nature of this problem, the team was able to find a solution.a) Despiteb) Althoughc) In spiteQuestion 3: The professor's lecture was so _______ that many students struggled to follow along.a) confusinglyb) confusionc) confusedSection 3: WritingInstructions: Write a short essay (about 300 words) on the following topic.Topic: The Impact of Artificial Intelligence on SocietyIn recent years, the advancement of artificial intelligence (AI) has significantly impacted various aspects of society. This essay will discuss the positive and negative effects of AI on different sectors, including the economy, healthcare, and education.Firstly, AI has revolutionized the economy by increasing efficiency and productivity. Automation of tasks that were once time-consuming allows businesses to operate at higher speeds and reduces costs. However, concerns arise regarding job displacement as AI systems continue to replace human labor in certain industries.Secondly, AI has transformed the healthcare sector by enabling more accurate medical diagnoses and personalized treatment plans. Machine learning algorithms can analyze vast amounts of patient data, leading to better outcomes and potentially saving lives. Nevertheless, ethicalconsiderations surrounding data privacy and AI decision-making must be addressed to ensure the responsible use of this technology.Lastly, AI has revolutionized education by providing personalized learning experiences. Intelligent tutoring systems can adapt to individual students' needs, enhancing their understanding and engagement. On the other hand, some argue that reliance on AI for education could lead to a lack of social interaction and critical thinking skills among students.In conclusion, artificial intelligence has undoubtedly had a significant impact on society. While it presents numerous benefits such as increased efficiency and improved healthcare outcomes, ethical considerations and potential challenges remain. To fully harness the potential of AI, it is crucial to find a balance between technological advancements and social responsibility.Conclusion:In conclusion, the computer-based English examination for the computer science doctoral degree is essential for assessing candidates' language proficiency. This article provided a sample of the examination, including reading comprehension, vocabulary, grammar, and writing sections. By familiarizing themselves with these sample questions and answers, candidates can better prepare for the exam and improve their chances of success. Good luck!。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:62

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:62

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题The tone of the article()the writer's mood at the time.问题1选项A.reproducedB.reflectedC.imaginedD.imitated【答案】B【解析】句意:这篇文章的语气反映了这位作者当时的情绪。

、考查动词辨析。

四个选项均为对应动词的过去式。

reproduce 复制,再生,生殖;reflect 反映,反射;imagine 想像,猜想,臆断;imitate 模仿,仿造。

空格处动词的宾语为the writer's mood (作者的情绪),因此B符合句意。

2.单选题Computers are employed to process census data and to()such financial business as collecting taxes.问题1选项A.facilitateB.fabricateC.fortifyD.falsify【答案】A【解析】句意:电脑被用来处理普查数据和辅助金融业务,比如收税。

考查动词辨析。

facilitate 促进,促使,使便利;fabricate 制造,伪造;fortify (尤指)筑城防御;(在物质或精神上)加强,增强;增强(感觉或态度);falsify 伪造,歪曲。

空格处动词的宾语为“financial business (金融业务)”,因此A符合句意。

3.单选题Study can help us look into the future and()confused thinking.问题1选项A.notifyB.simplifyC.clarifyD.justify【答案】C【解析】句意:学习能帮助我们展望未来,可以澄清混乱的思想。

考查动词辨析。

Notify通知,公布; simplify使简化,使简易; clarify 使更清晰易懂,阐明,澄清; justify证明…正确(或正当、有理),对…作出解释。

电子科技大学博士考试大纲

电子科技大学博士考试大纲

一、总体要求 二、内容及比例 1、概率论概要 概率空间、黎曼—斯蒂阶积分、随机变量、随机变量的数字特征、条件数学期望、收敛性与极 限定理。 2、随机过程的背景及定义 随机过程的工程背景、随机过程的定义及分类、随机过程的分布。 3、几类重要随机过程 独立过程与独立增量过程、正态过程、维纳过程、泊松过程。 二阶矩过程与均方微积分 4、二阶矩随机过程 均方极限、均方微分、均方导数、均方积分。 5、平稳随机过程 平稳过程概念、平稳过程的相关系数、功率谱、平稳过程的遍历性、平稳过程的谱密度、谱分 解、线性系统、平稳正态过程。 6、马尔可夫过程 马尔可夫过程概念、马尔可夫链与齐次马尔可夫链、齐次马氏链状态的分类与状态空间的分解。 三、题型及分值
电子科技大学博士研究生入学考试初试考试大纲 电子科技大学博士研究生入学考试初试考试大代数和概率论 180 分钟
考试形式 考试总分
笔试(闭卷) 100 分
参考书目
一、总体要求 二、内容及比例
《概率论讲义》 沈恒范 高等教育出版社 《概率论与数理统计》 盛聚 高等教育出版社 《概率论与数理统计》 徐全智 高等教育出版社 《高等代数》 北京大学数学系 高等教育出版社 《线性代数与空间解析几何》 黄廷祝 高等教育出版社
一、总体要求 二、内容及比例 1.复数和复变函数 复数,共轭复数,复数的四则运算,复数的几种表示法,模、幅角、幂、方根。要求熟练掌握 复数的四则运算和几种表示法的相互转化,掌握幂与方根的计算;理解复变函数与映射的概念;复 变函数的极限与连续性;了解复变函数极限与连续的概念,理解复变函数极限和连续的充要条件。 2.解析函数 复变函数的导数、解析函数,理解复变函数的导数和解析函数的概念;函数解析的充要条件, 要求掌握利用充要条件判别函数的可导性和解析性,掌握导数的计算;要求了解初等函数的定义, 计算及主要的性质。 3.复变函数的积分 复变函数积分的定义、性质,积分存在的条件,计算方法。要求掌握复变函数积分的一般计算 方法;柯西—古莎基本定理,原函数,不定积分;掌握柯西—古莎基本定理和解析函数定积分的计 算;复合闭路定理,闭路变形原理,柯西积分公式,高阶导数公式,要求掌握它们且利用它们计算 积分;调和函数,共轭调和函数,解析函数与调和函数的关系,理解解析函数与调和函数的关系, 掌握已知调和函数 U(或 V)求解析函数 f ( Z ) = U + iV 的方法。 4.级数 复数列的极限,复数项级数,绝对收敛与条件收敛,阿贝尔定理、收敛圆和收敛半径、收敛半 径的求法,幂级数的运算和性质,理解级数收敛、发散、绝对收敛、收敛圆的概念,掌握幂级数的 运算和性质;泰勒级数,泰勒定理。要求掌握几种主要的初等函数( e , sin Z , cos Z , (1 + Z ) ,

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:77

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:77

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题A great amount of work lias gone into()the Cathedral to its previous splendor.问题1选项A.refreshingB.restoringC.renovatingD.renewing【答案】B【解析】句意:大量的工作已经投入,为了使这个大教堂恢复到其以前的华丽。

考查动词辨析。

四个选项均为对应动词的现在分词形式。

refresh 更新,使精力恢复,使得到补充;restore 恢复,修复;restore to使恢复到…;renovate 更新,修复,革新,刷新;renew 使更新,续借,复兴。

由题干中关键词“to its previous splendor到其以前的华丽”可知B项正确。

2.单选题While typing Helen has a habit of stopping()to give her long and flowing hair smooth.问题1选项A.occasionallyB.simultaneouslyC.eventuallyD.promptly 【答案】A【解析】句意:当Helen打字的时候,她有一个习惯:偶尔停下来平整她飘逸的长发。

考查副词辨析。

occasionally 偶尔,有吋候;simultaneously 同吋地;eventually最终;promptly迅速地,敏捷地。

根据题干关键词“stop to give…(停下来去…)”可知A项符合句意。

3.单选题Over the last 25 years, British society has changed a great deal or at least many parts of it have. In some ways, however, very little lias changed, particularly where attitudes are concerned. Ideas about social class—whether a person is "working-class" or "middle-class"—is one area in which changes have been extremely slow.In the past, the working-class tended to be paid less than middle-class people, such as teachers and doctors. As a result of this and also of the fact that workers’jobs were generally much less secure, distinct differences in life-styles and attitudes came into existence. The typical working man would collect his wages on Friday evening and then, it was widely believed, having given his wife her "housekeeping", would go out and squander the rest on beer and betting.The stereotype of what a middle-class man did with his money was perhaps nearer the truth. He was and still is inclined to take a longer-term view. Not only did he regard buying a house as an important thing, but he also considered the education of his children as extremely important. Both of these provided him and his family with security. Only in very few cases did workers have the opportunity (or the education and training) to make such long-term plans. Nowadays, a great deal has changed. In a large number of cases factory workers earn as much, if not more, than their middle-class supervisors. Social security and laws, combined with a general rise in the standard of living since the mid-fifties of the 20th century, have made it less necessary than before to worry about "tomorrow". Working-class people seem slowly to be losing the feeling of inferiority they had in the past. In fact there has been a growing tendency in the past few years for the middle-classes to feel slightly ashamed of their position.The changes in both life-styles and attitudes are probably most easily seen amongst younger people. They generally tend to share very similar tastes in music and clothes, they spend their money in having a good time, and save for holidays or longer-term plans when necessary. There seems to be much less difference than in previous generations. Nevertheless, we still have a wide gap between the well-paid (whatever the type of job they may have) and the low-paid. As long as this gap exists, there will always be a possibility that new conflicts and jealousies will emerge, or rather that the old conflicts will re-appear, but between different groups.1.Which of the following is seen as the cause of class differences in the past?2.The writer seems to suggest that the description of()is closer to truth?3.According to the passage, which of the following is not a typical feature of the middleclass?4.Working-class people's sense of security increased as a result of all the following factors except?5.Which of the following statements is incorrect?问题1选项A.life style and occupationB.Attitude and incomeC.income and job securityD.job security and hobbies问题2选项A.middle -class ways of spending moneyB.working-class ways of spending the weekendC.working-class drinking habitsD.middle-class attitudes问题3选项A.desiring for securityB.Making long term plansC.having priorities in lifeD.saving money问题4选项A.better social securityB.more job opportunitiesC.higher living standardD.better legal protection.问题5选项A.Changes are slowly taking place in all sectors of the British society.B.The gap between working-class and middle-class young people is narrowing.C.difference in income will remain but those in occupation will disappear.D.middle-class people may sometimes feel inferior to working-class people.【答案】第1题:C第2题:A第3题:D第4题:B第5题:A【解析】1.细节事实题。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:85

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:85

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题As they don’t yet have a proven track record, their colleagues will be()to entrust them with important projects.问题1选项A.reluctantB.redundantC.relevantD.resistant【答案】A【解析】句意:由于他们没有过去工作表现的记录,所以其他同事不愿意将重要的项目交给他们。

考查形容词辨析。

Reluctant不情愿的,勉强的;redundant多余的,失业的,冗长的;relevant 相关的,切题的;resistant 反抗的,顽固的。

因此A符合句意。

2.单选题I recommend that the planning()until all the materials have been supplied.问题1选项A.is not startedB.will not be startedC.not be startedD.is not to be started 【答案】C【解析】句意:我建议应该在所有的材料己被提供后才启动这个计划。

语法题。

考查虚拟语气。

句子谓语为recommend,表示要求建议,这类动词所接的宾语从句一般用虚拟语气: (should) +原形动词,且should —般会省略,故选C。

3.单选题A rapid means of long-distance transportation became a necessity for the United State as settlement spread ever farther westward. The early trains were impractical curiosities, and for a long time the railroad companies met with troublesome mechanical problems. The most serious ones were the construction of rails able to bear the load, and the development of a safe, affective stopping system. Once these were solved, the railroad was established as the best means of land transportation. By 1860 there were thousands of miles of railroads crossing the eastern mountain ranges and reaching westward to the Mississippi. There were also regional southern and western lines.The high point in railroad building came with the construction of the first transcontinental system. In 1862 Congress authorized two western railroad companies to build lines from Nebraska westward and from California eastward to a meeting point, so as to complete a transcontinental crossing linking the Atlantic seaboard with the Pacific. The Government helped the railroads generously with money and land. Actual work on this project began four years later. The Central Pacific Company, starting from California, used Chinese labor, while the Union Pacific employed crews of Irish laborers. The two groups worked at remarkable speed, each trying to cover a greater distance than the other. In 1869 they met at a place called Promontory in what is now the state of Utah. Many visitors came there for the great occasion. There were joyous celebrations all over the country, with parades and the ringing of church bells to honor the great achievement.The railroad was very important in encouraging westward movement. It also helped build up industry and farming by moving raw materials and by distributing products rapidly to distant markets. In linking towns and people to one another, it helped unify the United States.1. The major problems with America’s railroad system in the middle I9lh century lay in().2. The building of the first transcontinental system().3. The best title for this passage would be().4. The construction of the transcontinental railroad took().5. What most likely made people think about a transcontinental railroad?问题1选项A.poor quality rails and unreliable stopping systemsck of financial support for developmentC.limited railroad linesck of a transcontinental railroad问题2选项A.brought about a rapid growth of industry and farming in the westB.attracted many visitors to the construction sitesC.attracted laborers from EuropeD.encouraged people to travel all over the country问题3选项A.Settlements Spread WestwardB.The Coast-to-Coast Railroad: A Vital LinkC.American Railroad HistoryD.The Importance of Trains in the American Economy问题4选项A.9 yearsB.7 yearsC.4 yearsD.3 years 问题5选项A.The possibility of government support for such a task.B.The need to explore Utah.C.The need to connect the east coast with the west.D.The need to develop the railroad industry in the west.【答案】第1题:A第2题:A第3题:B第4题:D第5题:C【解析】1.细节事实题。

2022年考研考博-考博英语-电子科技大学考试全真模拟全知识点汇编押题第五期(含答案)试卷号:88

2022年考研考博-考博英语-电子科技大学考试全真模拟全知识点汇编押题第五期(含答案)试卷号:88

2022年考研考博-考博英语-电子科技大学考试全真模拟全知识点汇编押题第五期(含答案)一.综合题(共15题)1.单选题The device can()different measurements by electronics means.问题1选项A.imitateB.copyC.mockD.fake【答案】A【解析】句意:这个设备能通过电子手段来模拟不同的尺寸。

考查动词辨析。

Imitate模仿,仿效,模仿(某人的讲话、举止); copy 复制,抄袭;mock 愚弄,嘲弄;fake 捏造,假装…的样子。

故A符合句意。

2.单选题The reason that the city attracts lots of inhabitants lies in that it’s a city of().问题1选项A.intensityB.diversityC.adversityD.necessity 【答案】B【解析】句意:这个城市吸引很多居民的原因在于它是一个多元化的城市。

考查名词辨析。

Intensity 强度,强烈;diversity 不同(点),多样性,多样化; adversity困境,逆境; necessity 必然,必要,需要。

因此B符合句意。

3.单选题Many years ago, I was interviewing for a CIO (Chief Information Officer) position at Brown University. Howard Swearer, the presiden t of Brown at that time, asked me: “What is the greatest(1)that you would bring to the position?” I answered: “I am multilingual.” He (2)at me for a moment, as if I had lost my mind entirely. I went on to(3)that I was capable of effectively(4)with faculty, with students, with vendors, with trustees, and with other administrators. The CIO needs to be able to interact effectively and be respected by a variety of audiences.Effectiveness of interaction is(5)on whether or not an individual can understand the(6)and problems being faced by a particular user. This is true on the academic side of the house, where one needs to understand the technology requirements and problems of a particle physicist, a classicist, or an economist. There are different(7)for data files, transmission speeds, and many other IT issues that directly affect the scholarship of these varying disciplines. The ability to(8)some of these scholarly requirements is(9)to being viewed as a partner in the academic enterprise rather than just as some bureaucrat who has(10)for the IT environment on campus.问题1选项A.trengthB.newsC.possibilityD.change问题2选项A.nterviewedB.staredC.wonderedD.angered问题3选项A.nswerB.explainC.indicateD.demonstrate问题4选项A.alkingB.speakingC.cooperatingmunicating问题5选项A.ependedB.basedC.resultedD.taken问题6选项A.hocksB.worriesC.questionsD.concerns问题7选项A.eedsB.issuesC.elementsD.concerns问题8选项A.nowB.find outC.look forD.understand问题9选项A.pecialB.inevitableC.essentialD.required问题10选项A.oncernsB.worriesC.responsibilityD.confidence【答案】第1题:A第2题:B第3题:B第4题:D第5题:B第6题:D第7题:A第8题:D第9题:C第10题:C【解析】1.名词辨析。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:99

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:99

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题The company expanded its business into Europe, hoping to().问题1选项A.boostB.encourageC.urgeD.accelerate【答案】A【解析】句意:这家公司把它的业务扩展到了欧洲,希望能够增加市场份额。

考查动词辨析。

Boost 使增长,使兴旺,偷窃; encourage鼓励,激励; urge催促,驱策; accelerate 加快,加速。

空格的宾语为“its market share (市场份额)”,因此A符合句意。

2.翻译题A popular way of mustering innovative and fresh ideas is to hold a brainstorming session —but according to a paper published recently in Applied Cognitive Psychology, this may not be the best approach. The study, which was carried out by Nicholas Kohn of the University of Texas at Arlington and Steven Smith of Texas A&M University, suggests that instead of enhancing creativity. brainstoiT nin.u sessions may give rise to a “collaborative fixation” on certain ideas.(1)In keeping with previous studies, the authors first found that participants produced fewer ideas in total when taking part in a brainstorming session than if they had been working separately. The difference was as high as 44% in the first 5 minutes of a brainstorming session. The authors also found that when working separately particii)ants explored a greater variety of ideas, up to 55% more idea categories than dm.ing brainstomiing sessions. (2)In a second experiment, the researchers found that participants in a brainstorming session tended to conform to ideas to which they were exposed, and the rate of conformity increased as the number of ideas exposed increased. (3) The auth ors wrote in their paper “Fixation to other people’s ideas can occur unconsciously and lead to you suggesting ideas that mimic your brainstoniiin»partners.’’ (4)Thus, you potentially become less creative,” Kohn explains in an accompanying press release. T his doesn’t necessarily mean that you should ban brainstorming sessions from your lab meetings. You might just need to adjust the format. It seems odd, but, depending on what you want to achieve, the best approach might be to put everyone in a separate roo m. “Assuming it is desirable to have a wide variety of ideas or solutions to a problem...then one should split the brainstorming group into non-interacting individuals, avoiding a group session,” the authors write in their research paper. “On the other hand, if the goal is to explore a few categories in depth, then interacting among the members should be encouraged. Also, taking a break might help alleviate fixation, leading to an improvement in ideation, especially in temis of the quantity and variety of i deas. (5)’’【答案】1.集体研讨会议不但没有提高创造性,反而可能在某些想法上会引起“合作的固定”。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:47

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:47

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题We()managed to have people accept our theory after a long, hard struggle.问题1选项A.momentarilyB.suddenlyC.graciouslyD.gradually【答案】D【解析】句意:经过长期的艰苦努力之后,我们逐渐让他们接了受我们的理论。

考查副词辨析。

momentarily 顷刻之间,马上;suddenly意外地,忽然地;graciously优雅地,慈样地;gradually逐步地,渐渐地。

根据后文的after a long, hard struggle (长期的艰苦努力之后)可知D正确。

2.单选题It takes much time to solve the problem one by one. Can we generalize common()to apply to similar problems?问题1选项A.meansB.techniquesC.tipsD.solutions【答案】D【解析】句意:一个接一个地解决问题需要很多吋间。

我们能归纳出适用于所有类似问题的通用解决方法吗?考查名词辨析。

means 手段,方法;technique 技巧,技艺,工艺;tip尖端,尖儿,端;solution 解决方案,溶液,溶解。

根据关键信息“problem (问题)”可知D符合句意。

3.单选题Do you have any()about what living beings on other planets would be like?问题1选项A.idealprehensionC.notionD.intelligence【答案】C【解析】句意:你对生活在其他星球上的生物的样子有什么概念吗?考查名词辨析。

电子科技大学泛函分析(江泽坚)课后题集答案解析

电子科技大学泛函分析(江泽坚)课后题集答案解析

P46:第一章习题:1.验证(),()d m 满足距离定义。

解:设{}i x ξ=,{}i y η=属于X ,α是数,()1,sup .j j j d x y ξη≥=-(1)对j ∀,有0j j ξη-≥,所以1sup j j j ξη≥-,(),0d x y ≥,且1sup 00j j j j j j j ξηξηξη≥-=⇔-=⇔=,即(),0d x y =当且仅当.x y =(2) ()()11,sup sup ,j j j j j j d x y d y x ξηηξ≥≥=-=-=;(3)设{}i z ζ=()()1111,sup sup ()()sup sup ,(,)j j j j j j j j j j j j j j d x z d x y d y z ξζηξξζηξξζ≥≥≥≥=-≤-+-≤-+-=+综上(1),(2),(3),(),d 满足距离定义。

3.试证明:在空间()s 中的收敛等价于坐标收敛。

证:设{}()(),1,2,n n jx s n ξ=∈=,{}()(0)0jx s ξ=∈,()⇒若0n x x →,则必有()(0)lim ,1,2,n j j n j ξξ→∞==,否则,j N +∃∈,00ε>,与正整数列的子序列{}1k k n ∞=,使()(0)0,1,2,k n j j k ξξε-≥=,因为()1tf t t=+是单调递增, 所以()()(0)0()(0)11,,1,2,2211k k k n j j n j j n j j d x x k ξξεεξξ-≥⋅≥⋅=++-,这与()0,0k n d x x →矛盾, 故()s 中的收敛可推出坐标收敛。

()⇐若()(0)lim ,1,2,n j j n j ξξ→∞==,则对j ∀,0ε∀>,0N N +∃∈,0n N ∀>,()(0)2n j jεξξ-<,()()(0)0()(0)1111,,1,2,2211n j j n j j n j j j j d x x k ξξεεξξ∞∞==-=⋅<⋅=++-∑∑,由ε的任意性得()0,0.n d x x → 故命题得证。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:63

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:63

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题Some criminals were printing()dollar bills until they were arrested.问题1选项A.decentB.fakeC.patentD.suspicious【答案】B【解析】句意:有些罪犯直到被逮捕吋还正在印刷伪造的美钞。

考查形容词辨析。

decent像样的,相当不错的,正派的,得体的,相当好的;fake 假的,伪造的,冒充的;patent 专利的,显然的;suspicious 可疑的,怀疑的,多疑的。

故B符合句意。

2.单选题We must()that the procedure is followed as rigidly as possible.问题1选项A.secureB.ensureC.assureD.issue 【答案】B【解析】句意:我们必须确保这个程序尽可能被严格遵循。

考查动词辨析。

secure 保护,弄到;ensure 保证,确保,使安全; assure 保证,担保,使确信(侧重指消除某人思想上的怀疑或担心);issue 发布。

因此B符合句意。

3.单选题Fuel scarcities()automobile designers to develop small-displacement vehicles for public use.问题1选项A.promptedB.encouragedC.fomentedD.spotlighted【答案】A【解析】句意:燃料短缺促使汽车设计师开发供公众使用的小排量汽车。

考查动词辨析。

选项均为对应动词的过去式。

prompt 提示,促使,激起;encourage鼓励,激励;foment 煽动,挑起;;spotlight聚光照明,使公众注意。

因此A符合句意。

4.单选题Please do not be()by his bad manners since he is merely trying to attract attention.问题1选项A.disregardedB.distortedC.irritatedD.intervened【答案】C【解析】句意:他只是想引起注意,所以请不要因为他的不礼貌而生气。

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:95

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)试题号:95

2022年考研考博-考博英语-电子科技大学考试全真模拟易错、难点剖析AB卷(带答案)一.综合题(共15题)1.单选题My daughter lias walked eight miles today. We never guessed that she could walk()far.问题1选项A./B.suchC.thatD.as【答案】C【解析】句意:我女儿今天己经步行了8英里。

我们从未想到她能步行那么远。

考查连词辨析。

Such是代词或限定词表示“这样(的)”,一般不修饰形容词;that (与表数量或范围的形容词和副词连用)那样,那么;as 同样地;和……一样的。

因此C符合句意。

2.单选题Fuel scarcities()automobile designers to develop small-displacement vehicles for public use.问题1选项A.promptedB.encouragedC.fomentedD.spotlighted 【答案】A【解析】句意:燃料短缺促使汽车设计师开发供公众使用的小排量汽车。

考查动词辨析。

选项均为对应动词的过去式。

prompt 提示,促使,激起;encourage鼓励,激励;foment 煽动,挑起;;spotlight聚光照明,使公众注意。

因此A符合句意。

3.单选题We are dealing with two different perspectives that(), intersect, but don’t seem to yield a synthesis.问题1选项A.overrunB.overlapC.overworkD.overuse【答案】B【解析】句意:我们正在处理有部分重叠、交叉却似乎不能生成综合体的两种不同的透视图。

考查动词辨析。

Overrun 泛滥,横行,肆虐,多用(时间、钱财等),超时;overlap部分重叠,部分地同时发生;overwork工作过度;overuse 使用……过度(或过久)。

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An A sup An A x
x 1
sup lim x 1 m
An Am x
lim sup m x 1
An Am x
lim m
An Am
0
当 n 。证毕。
4、证明:令 X1
X, 1
, X2
正定性:对任意的 A L(X ,Y ) , x X ,
A sup Ax 0
x 1
A 0 当且仅当 A 0 。
齐次性:对任意的常数
A sup Ax sup Ax A
x 1
x 1
三角不等式:对任意的 A, B L(X ,Y ) ,
A B sup A B x sup Ax Bx sup Ax sup Bx A B
空间。
4、(20 分)设 X 为有限维赋范空间,证明: X 上任意两个范数都是
等价的。
5、(20 分)设 H 是 Hilbert 空间, (x, y)是 H 上有界的共轭双线性 泛函,证明:对任意的 x 与 y ,存在唯一的有界线性算子 A 满足 (x, y) (Ax, y) 。
泛函分析答案
x 1
x 1
x 1
x 1
从而 L(X ,Y ) 按算子范数形成赋范线性空间,下证 L(X ,Y ) 是完备的。

An
n1

L(
X
,Y
)
中的
Cauchy
序列,则对任何的
x

X
,从
An x Am x An Am x
可见 An
x n1
是Y
中Байду номын сангаас
Cauchy
序列,而Y
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y y

就是正规正交集,由
Bessel
不等

式,
2
x,
y y

x2

x, y x y
且等号成立当且仅当
x
可由


y y

线性表出,即等号成立当且仅当
x

与 y 线性相关。
3、证明:首先证明 L(X ,Y ) 按算子范数形成赋范线性空间。
(x, y) ( y, Ax)

(x, y) (Ax, y) ,当 x, y H
不难验证,如此定义的 A 确是,当 H 上的有界线性算子,至于唯一
性是显然的。证毕。
电子科技大学 2018 年攻读博士学位研究生入学考试试题
科目:3043 泛函分析 注:请将答案写在答题纸上,在本试卷上作答一律无效。 1、(20 分)设 f (x) C[0,1] , f (x) 可导且满足 f ' (x) a 1,证明 f (x)是压缩的。
2、(20 分)设 X 为内积空间,证明对 X 中任意两个向量 x, y 都有 (x, y) x y ,若等式成立当且仅当 x 与 y 线性相关。 3、(20 分)设 X 为赋范线性空间,Y 为 Banach 空间, L(X ,Y ) 是从 X 到Y 的全体有界线性算子,证明 L(X ,Y ) 按算子范数形成 Banach
y
Y

使
lim
n
An x

y
现在定义 Ax y 。易见 A 是线性的,又因为赋范线性空间中的 Cauchy
序列是有界的,故存在常数 M 0 ,使 An M , n 1, 2,。则
Ax
lim n
An x
lim n
An
x M x
可见 A L(X ,Y ) 。又
X, 2
,显然必存在有一个范数
较强,不妨假设存在一个 M 0 ,使得
x M x
2
1
取单位算子 I L X1, X2 ,这时有
Ix M x
2
1
故 I 是有界线性算子,显然 I 是双射,由逆算子定理可知, I 存在逆
算子 I 1 ,且有界,因而
I 1x M x
1
2
所以 与 等价。
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而 a 1,所以映射 f (x)是压缩的。
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y

0
1
2
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f ( y) ( y, z f ) ,当 y H 这个 z f 是由 f ,从而由 x 唯一确定的。定义 Ax z f ,则
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