第二次大作业

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数值分析第二次大作业——编写ln函数实验报告

为一个整体，将 ln(a)进行 Taylor 级数分解，进而按式计算可以求得 ln(x)的值。由于我们选取级数的前 n 项和近似 ln(a)，则有：
Rn (a
1)

(1)n
(a 1)n1 n 1
…；
|
Rn
(a
1)
||
(a 1)n1 n 1
|
。
2
自 92 乔晖 2009011414
精度为 20 位，即 h4 1020 。
int * GetNumber() {return number;}
//获得大数中的整数数组
bool GetSgn() const {return sgn;}
//获得大数的符号
bool IsZero();
//判断大数是否为 0
CBigNumber Reverse() {sgn = !sgn;return *this;} //取相反数
数值分析——编写 ln 函数
实验报告
自 92 乔晖 2009011414
自 92 乔晖 2009011414
数值分析——编写 ln 函数实验报告
目录
一、实验任务 ................................................... 2
二、编译环境 ................................................... 2
1u
x 1
35
5
自 92 乔晖 2009011414
数值分析——编写 ln 函数实验报告
其前 n 项和，近似可得 ln(x)的值。
基于以上原理，可以设计迭代算法，累加 2u2i1 得到前 n 项和。每次计算后，判断计 2i 1

2022川大网教大学英语4第二次作业

大学英语（四）第二次作业班级：22春(批次)202203学期成绩：100分一.单选题（共40题,96.0分）1- I'd like to book a room, please.- _______A、Single or double?B、Good or bad?C、Which room?D、We don't have books here.我的答案：A得分：2.4分2-Hello! Can I get a seat on the 8 pm flight to Detroit? - _______A、Hello! International AirlineB、You'd better look up the schedule firstC、I'm sorry, but it's completely bookedD、I'm afraid you have to change我的答案：C得分：2.4分3- What time is the next flight to Washington? - _______A、It’s a smaller one.B、It’s too late .C、It’s 1.45 pm.D、It sounds good.我的答案：C得分：2.4分4- Passport, please?- _______A、It is here.B、What do you want?C、Here you are.D、No, you can’t.我的答案：C得分：2.4分5- I didn't know my identity card(身份证)was needed, sir. - ______A、That's sorry.B、I don't believe you.C、Sorry, but that's no excuse.D、You can't say that.我的答案：C得分：2.4分6— Oh dear! I've just broken a window.— _______! It can't be helped.A、GreatB、Never mindC、That's fineD、Not at all我的答案：B得分：2.4分7- What do you think of this novel? - _______A、I've read it.B、It's well-written.C、It was written by my uncle.D、I bought it yesterday.我的答案：B得分：2.4分8- Excuse me, how much is the jacket? - It's 499 Yuan. _______A、Oh, no. That's OK!B、How do you like it?C、Which do you prefer?D、Would you like to try it on?我的答案：D得分：2.4分9- Hello, I would like to open an account.- _______A、Which account do you want to see?B、Have you make up your mind?C、What kind of account do you have in mind?D、You’re welcome.我的答案：C得分：2.4分10- Would you please show me your bankbook? - _______A、Sorry, I have no idea.B、Here you are.C、Come with me.D、Yes, I'd like to.我的答案：B得分：2.4分11- I feel sick.- _______- I'm not sure, but I have got a bad headache.A、I'm sorry to hear that.B、How are you feeling now?C、Do you have a high temperature?D、How long have you been away?我的答案：C得分：2.4分12- Must we hand in our homework now?- _______A、Yes, you will.B、Yes, you mustn’t .C、No, you needn’t.D、No, you mustn’t.我的答案：C得分：2.4分13-Excuse me. Is this table taken?-______A、We haven't booked the dishesB、We haven't ordered the dishesC、Yeah. I'm saving these seats for friendsD、Yeah. I'm hungry我的答案：C得分：2.4分14-Let me see inside your carry-on bag. - _______A、Just a few personal belongings.B、You have no right.C、It’s my privacy.D、Is it necessary?我的答案：A得分：2.4分15If he _______, he would have signed his name in the cornerA、painted that pictureB、paints that pictureC、would have painted that pictureD、had painted that picture我的答案：D得分：2.4分16It’s already 5 o’clock. Don’t you think it’s about time _______?A、we are going homeB、we go homeC、we went homeD、we can go home我的答案：C得分：2.4分17It has been proposed that we _______ our decision until the next meetingA、delayedB、delayC、can delayD、are to delay我的答案：B得分：2.4分18I wish I _______ what to doA、knewB、have knownC、knowD、would know我的答案：A得分：2.4分19Not until I began to work _______ how much time I had wastedA、didn’t I realizeB、did I realizeC、I didn’t realizedD、I realized我的答案：B得分：2.4分20His answer is not correct, and _______A、neither am IB、either is mineC、neither is mineD、mine is neither我的答案：C得分：2.4分21Hardly _______ the railway station when the train startedA、did I reachB、had I reachedC、I reachedD、I had reached我的答案：B得分：2.4分22She suffered temporary loss of _______ after being struck on the headA、viewB、visionC、eyeD、illusion我的答案：B得分：2.4分23The company’s move to new offices is _______A、in turnB、in effectC、in natureD、in process24- _______ I take the newspaper away?- No, you mustn't. You _______ read it only here.A、Must; canB、May; canC、Need; mustD、Must; must我的答案：B得分：2.4分25This is the third week _______ the dustmen haven’t come fo r the rubbishA、thatB、whenC、whichD、on which26With the _______ of Mary, all the girl students are eager to go to the partyA、exhibitionB、exceptionC、exceptD、reception我的答案：B得分：2.4分27You needn't make such a funny noise, _______?A、don't youB、doesn't itC、need youD、need it我的答案：C得分：2.4分28Sorry, I don't know he is a friend of ________A、your brotherB、your brothersC、your brother's friendD、your brother's我的答案：D得分：2.4分29_______ they met each other and became good friendsA、It was in the countryside whereB、Being in the countrysideC、It was in the countryside whenD、It was in the countryside that我的答案：D得分：2.4分30It _______ a retired worker that she was brought up after her mother’s death.A、isB、wasC、areD、were我的答案：B得分：2.4分31The man, together with two girls, _______ by the policeA、has arrestedB、was arrestedC、are arrestedD、have arrested我的答案：B得分：2.4分32- Do you want to wait?- Five days _______ too long for me to wait.A、wasB、wereC、isD、are我的答案：C得分：2.4分33A number of people _______ at the street cornerA、amB、isC、areD、be我的答案：C得分：2.4分34Neither the students nor the teacher _______ got the right answerA、haveB、hasC、isD、are我的答案：B得分：2.4分35Only after I had reached the supermarket _______ that I had forgotten to take my purse with meA、I had realizedB、I realizedC、I have realizedD、did I realize我的答案：D得分：2.4分36Physics _______ always my strong pointA、isB、areC、beingD、to be我的答案：A得分：2.4分37You'd better wear more clothes. It's ______ cold todayA、much tooB、too muchC、very muchD、much very我的答案：A得分：2.4分38Her reaction to the child’s bad behavior was unnecessarily _______A、abundantB、fluencyC、rationalD、hash我的答案：D得分：2.4分39I won’t make the _______ mistake next timeA、likeB、sameC、nearD、similar我的答案：B得分：2.4分40There is an old saying that husbands and wives start to look and behave like each other after a time. I don't know if this was true of my mother and father.Both of my parents had brown hair and brown eyes and low voices. My father, ______, was eight years older than my mother and taller and thinner. He was built as straight as an arrow. Mymother was shorter and had a rounder and fuller face and she looked as soft as a pillow.My mother was quieter and talked less than my father did. She was also a much more patient person than my father. My father was more experienced in life. He was ______ to doing everything quickly. My mother, on the other hand, worked and spoke more slowly.They were fond of nature and sports, such as walking, gardening and swimming. They were both ______ in reading and music, but my father preferred history books, while my mother liked to read romantic novels. In music, their types were similar, and they were never proud of listening to it. Most of the time they were in agreement on bringing ______ their children. They both believed in giving them love and neither one believed in punishing them physically. At times, their personalities were very much alike, but at other times, they seemed very ______. Perhaps that is why none of their children knows which parent he looks or behaves like.（根据文章，将下面五个选项按照正确的顺序填在原文中）A. howeverB. interestedC. upD. usedE. differentA、ABDECB、ADBCEC、CDABED、BACED我的答案：B得分：2.4分二.阅读理解（共1题,4.0分）1In 1920, barely out of his teens, Alfred Hitchcock went to work for an American film company which had opened astudio in Islington, London. His first job at the studio was writing captions （脚本） for silent movies. Within two years, he was writing scripts（剧本） and working as an assistant director. For the rest of the 1920s, Hitchcock worked on one film after another in Britain and Germany. Filming was often arough-and-ready（匆忙做成的） affair and the assistant directormissing, Hitchcock became a cameraman. A scene needed rewriting, Hitchcock rewrote it. Someone needed to be in charge of money when the film crew was on location, Hitchcock looked after the money.At the same time, this being the era of silent movies, Hitchcock was learning the language of cinema: telling a story －not through dialogue, but through visual images（视觉影象）. This led to his success later.When he began to direct his own films, first in Britain and later in Hollywood, he was determined to make films that held the audience's attention and kept tension（紧张感）. He succeeded. Hitchcock's ability to put you on the edge of your seat makes him one of the greatest makers of suspense（悬念） movies.（以下为试题题干）(1) [判断题]※Alfred Hitchcock's first job at the studio was writing captions for silent movies.(2) [判断题]※According to the context, "step in and plug gaps" (in Line 3, Para. 2) means asking for one's help.(3) [判断题]※Telling a story through dialogue prepared Hitchcock for his success later.(4) [判断题]※He was determined to draw the audience's attention and keep tension in his film-making.(5) [判断题]※He had taken up different jobs before he succeeded.。

操作系统第二次作业题及答案.doc

第2次作业一、单项选择题（本大题共40分，共20小题，每小题2分）1.设备驱动程序负责接收和分析从设备分配转来的信息以及设备控制块等内容。

（）不是设备驱动程序的功能。

A.根据请求传送的数据量，组织I/O缓冲队列B.利用T/0缓冲，对数据进行加工C.启动设备进行I/O操作D.I/O设备中断处理2.解决死锁的途径是（）A.立即关机排除故障B.立即关机再重新开机C.不要共享资源，增加独占资源D.运行检测程序并恢复系统3.吋间片一般应用于（）。

是A.批处理操作系统B.分时操作系统C.实时操作系统D.以上都不是4.磁带上的文件一般只能（）A・随机存取B•顺序存取C.直接存取D.以字节为单位存取5.下面关于临界区概念论述正确的是：（）A.临界区是指进程中用于实现进程互斥的那段程序代码氏临界区是指进程中用于实现进程同步的那段程序代码C.临界区是指进程中用于实现进程通信的那段程序代码D.临界区是指进程中用于访问公用数据（临界资源）的那段程序代码6.配置了操作系统的计算机是一台比原来的物理计算机功能更强的计算机，这样的计算机只是一台逻辑上的计算机，称为（）计算机。

A.并行B.真实C.虚拟D.共享7.内存和外存容量之和与虚拟存储器容量相比其大小关系是（）A.前者比后者大B.前者比后者小C.二者相等D.不一定8.把独占性设备改造成能为若干个用户共享的设备，这种设备称为（）A.存储设备B.系统设备C ・用户设备D.虚拟设备9. 为实现对缓冲区buf 访问的同步，下叙述中正确的是A. 读进程从buf 中读出数据前，应用对写进程信号量进行P 操作；B. 读进程从buf 中读出数据前，应用对写进程信号量进行V 操作；C. 读进程从buf 中读岀数据后，应用对写进程信号量进行P 操作；D. 读进程从buf 屮读出数据后，应用对写进程信号量进行V 操作；10.（）大多用于对信息的及时性要求比较严格并且很少会对所有数据进行处理的应用程序中。

离散随机信号处理第二次大作业

2000
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w(3) vs -a(3) w(2) vs -a(2) w(1) vs -a(1)
w(4) vs a(4) w(3) vs a(3) w(2) vs a(2) w(1) vs a(1)
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组参数。研究LMS 算法的跟踪能力。
4) 用 RLS 算法重新做（3）。
1.分析：
本实验旨在比较 LMS 算法和RLS 算法的性能差异，结合模型参数辨识的具体问题，进一步理解两种算法的思路、复杂度以及应用场景。在实验中，避开起始瞬态点以得到平稳的随机信号。实验中要对比区分两个信号源的差异，1 为宽带过程，2 为窄带过程。自适应线性前向滤波器设计如下——通过计算机仿真产生白噪声，驱动各AR 模型，产生平稳的随机信号，使该信号通过自适应预测器，运用具体的自适应滤波算法得到对应的模型参数。其中 v（n）为白噪声，自适应滤波器取为4 阶的，具体自适应滤波算法体现在自适应滤波模块内部。

北航数值分析第二次大作业(带双步位移的QR方法)

一、算法设计方案：按题目要求，本程序运用带双步位移的QR方法求解给定矩阵的特征值，并对每一实特征值，求解其相应的特征向量。

总体思路：1）初始化矩阵首先需要将需要求解的矩阵输入程序。

为了防止矩阵在后面的计算中被破坏保存A[][]。

2）对给定的矩阵进行拟上三角化为了尽量减少计算量，提高程序的运行效率，在对矩阵进行QR分解之前，先进行拟上三角化。

由于矩阵的QR 分解不改变矩阵的结构，所以具有拟上三角形状的矩阵的QR分解可以减少大量的计算量。

这里用函数void QuasiTriangularization()来实现，函数形参为double型N维方阵double a[][N]。

3）对拟上三角化后的矩阵进行QR分解对拟上三角化的矩阵进行QR分解会大大减小计算量。

用子程序void QR_decomposition()来实现，将Q、R设为形参，然后将计算出来的结果传入Q和R，然后求出RQ乘积。

4）对拟上三角化后的矩阵进行带双步位移的QR分解为了加速收敛，对QR分解引入双步位移，适当选取位移量，可以避免进行复数运算。

为了进一步减少计算量，在每次进行QR分解之前，先判断是否可以直接得到矩阵的一个特征值或者通过简单的运算得到矩阵的一对特征值。

若可以，则得到特征值，同时对矩阵进行降阶处理；若不可以，则进行QR分解。

这里用函数intTwoStepDisplacement_QR()来实现。

这是用来存储计算得到的特征值的二维数组。

考虑到特征值可能为复数，因此将所有特征值均当成复数处理。

此函数中，QR分解部分用子函数void QR_decompositionMk()实现。

这里形参有三个，分别用来传递引入双步位移后的Mk阵，A矩阵，以及当前目标矩阵的维数m。

5）计算特征向量得到特征值后，计算实特征值相应的特征向量。

这里判断所得特征值的虚数部分是否为零。

求实特征值的特征向量采用求解相应的方程组((A-λI)x=0)的方法。

因此先初始化矩阵Array，计算(A-λI)，再求解方程组。

大学英语B第二次大作业(客观题)

大学英语（B）（本，2019春）A. Very well.B. By taking a course.C. In the libraryD. In the morning反馈【解析】根据问句中的疑问词How可知答语应该是某种方式，所以选B。

句意："---马克是怎样学西班牙的？----通过选课学习的。

”题目2正确获得3分中的3分2. --You know, I have three kids now.--___________________选择一项：A. That's terrific!B. Well, I've grown a mustache.C. Say, you've really changed your mind.D. Well, I gave up drinking.反馈【解析】此题可用排除法进行解题。

上文说"你知道吗，我现在有3个孩子”，这属于好事情，所以答语用That's terrific.（太好了）表示积极回应。

题目3正确获得3分中的3分3. --John, 回答B?--Oh, that's my father! And beside him, my mother.A. which is thatB. who's talking over thereC. what are they doingD. what is the person over there反馈【解析】根据下文回答"那是我爸爸”来判断，上文在问"某人是谁（Who's...?）”。

句意："----约翰，谁在那里说话？----哦，那是我爸爸，他旁边是我妈妈。

”题目4正确获得3分中的3分4. --How do you do? Glad to meet you.反馈【解析】此题考查如何回应问候。

针对问候语"How do you do”，只要回答"How do you do”就可以。

线性系统第二次大作业

目录第一章矩阵论基础........................................................................................... - 1 -1.1子空间与不变子空间 ........................................................................... - 1 -1.2 线性定常系统解的结构....................................................................... - 1 - 第二章控制论的相关概念 ............................................................................... - 2 -2.1稳定性理论........................................................................................... - 2 -2.2 能控性与能观性 .................................................................................. - 2 - 第三章基于不变子空间的系统分析 ................................................................ - 3 -3.1 不变子空间与系统的解集结构 ........................................................... - 3 -3.2不变子空间与能控能观性.................................................................... - 4 -3.2.1 不变子空间与能控性 ....................................................................... - 4 -3.3不变子空间与卡尔曼分解.................................................................... - 6 - 第四章BIBO稳定性和李雅普诺夫稳定的关系 ............................................ - 10 -4.1 BIBO稳定的充要条件....................................................................... - 10 -4.2 李雅普诺夫稳定的充要条件............................................................. - 10 -4.3 渐进稳定的充要条件 ........................................................................ - 11 -4.4 内部稳定必定BIBO稳定 ................................................................. - 11 -4.5 外部稳定不一定内部稳定................................................................. - 11 -4.6 临界稳定不一定BIBO稳定 ............................................................. - 12 -4.7 特定初态的内部稳定性..................................................................... - 14 -4.8 内部稳定与BIBO稳定等价条件...................................................... - 14 -4.9 初始状态，输入矩阵，输出矩阵对状态稳定的影响....................... - 15 - 第五章总结 .................................................................................................... - 17 - 第六章参考文献............................................................................................. - 18 -第一章矩阵论基础1.1子空间与不变子空间1.1.1子空间设W 是数域P 上线性空间V 的非空子集，则W 是V 的线性子空间的充要条件是：a) 若,W W ∈+∈，则αβαβ b) ,W k P k W ∈∈∈，则αα1.2.1不变子空间设T 是线性空间V 的一个线性变换，又W 是V 的一个子空间，若对于任意W ∈，α都有T W ∈α，即：()T W W ⊂则称W 是线性变换T 的不变子空间。

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第二次大作业
一、填空题
１.（）是指人们关于基本价值的立场、取向、态度、信念、理想系统。

２.（）是指一种哲学思想或道德标准，用来辨别行为的善与恶，即这会关系中判断行为的一种道德标准。

３.（）是指风俗习惯及社会传统，它是调节和约束人们行为的一种社会规范。

４.社会工作伦理困境是指由于社会工作者所秉承的（）之间的不一致而产生的困顿局面。

５.社会工作专业的道德特质决定了社会工作者的活动必然是以促进他人的（）为目标。

二、选择题
１.下列（）情况下可以有限度打破“保密”原则
A .同事跟你聊天时打听你的服务对象的隐私资料
B .你的服务对象对你透露他和朋友将参加械斗，但他希望你保密
C .服务对象向你透露他可能自杀
D. 法庭要求作证
２.社会工作者杨安今天约一名服务对象商讨最低生活保障申请事宜，但是他今天觉得父亲很需要他的照顾而想请假。

他处于一种艰难的选择中，你认为这是社会工作中伦理难题的什么问题。

（）
A.自决原则和知情同意
B.价值中立和价值介入
C.个人利益和社会责任
D.保密问题
３.伦理抉择基本过程主要包含（）要素
A.明确价值观和基本伦理原则
B. 理清涉及的人员、组织和利益关系
C.评估各种可能的计划和方案
D. 记录并总结抉择的结果
４.高二学生小明在和社会工作者交谈中透露了他想自杀的想法，并要求社会工作者保密，下列社会工作者的做法中，较为妥当的是()。

A．告诉小明的老师和同学
B．告诉小明的父母
C．和社会工作机构同事商讨帮助小明的方法
D．和小明进行深入沟通，如果不能阻止其自杀意念，及时向所在社工机构报告
５.张女士离婚后，独自带着女儿小飞生活。

最近，张女士认识了一位陈先生，双方感觉不错，有意结合，可是却遭到了小飞的强烈反对。

张女士想请社会工作者帮她出个主意，社会工作者的适当做法是（）。

A．深入了解事情的情况，鼓励张女士做出决定
B．为了孩子的利益，反对张女士再婚
C．让张女士先散心，把事情放一段再说
D．为了张女士的幸福，支持张女士再婚
三、简答题
１.简述伦理困境的成因。

２.简述价值观体系的构成。

３.简述价值、伦理与道德之间的关系
四、论述题
试述社会工作实践中的伦理困境的类型。