《电大机电控制工程基础作业4.doc》由会员分享，可在线阅读，更多相关《电大机电控制工程基础作业4.doc（6页珍藏版）》请在三一办公上搜索。
1、专业好文档机电控制工程基础作业4单项选择题 第1题 PID控制器的传递函数形式是（）。 A、5+3s B、5+3/s C、5+3s+3/s D、5+1/s+1 答案：C 第2题 拉氏变换将时间函数转换为（）。 A、正弦函数 B、单位阶跃函数 C、单位脉冲函数 D、复变函数 答案：D 第3题 线性定常系统的传递函数，是在零初始条件下的（）。 A、系统输出信号与输入信号之比 B、信号输入信号与输出信号之比 C、系统输入信号的拉氏变换与输出信号的拉氏变换之比 D、系统输出信号的拉氏变换与输入信号的拉氏变换之比 答案：D 第4题 PID控制器中，积分控制的作用是（）。 A、客服对象的延迟和惯性 B、能
2、使控制过程为无差控制 C、减少控制过程的动态偏差 D、使过程较快速的达到稳定 答案：C 第5题 当二阶系统的根分布在右半根平面时，系统的阻尼比为（）。 A、阻尼比小于0 B、阻尼比等于0 C、阻尼比在0和1之间 D、阻尼比大于1 答案：D 第6题 时域分析法中最常用的典型输入信号是（）。 A、脉冲函数 B、斜坡函数 C、阶跃信号 D、正弦函数 答案：C 第7题 传递函数反映了系统的动态性能，它与下列哪些因素有关？（） A、输入信号 B、初始条件 C、系统的结构参数 D、输入信号和初始条件 答案：C 第8题 采用系统的输入、输出微分方程对系统进行数学描述是（）。 A、系统各变量的动态描述 B、系
3、统的外部描述 C、系统的内部描述 D、系统的内部和外部描述 答案：A 第9题 根据给定值信号的特点分类，控制系统可以分为（）。 A、恒值控制系统、随动控制系统和程序控制系统 B、反馈控制系统、前馈控制系统和复合控制系统 C、最优控制系统和模糊控制系统 D、连续控制系统和离散控制系统 答案：A 第10题 系统特征方程式的所有根均在根平面的左半部是系统稳定的( )。 A、充分条件 B、必要条件 C、充分必要条件 D、以上都不是 答案：A 第11题 脉冲函数拉氏变换为( )。 A、0 B、无穷大 C、常数 D、变量 答案：B 第12题 理想微分环节对数幅频特性曲线是一条斜率为( )。 A、20db/
4、dec,通过=1点的直线 B、负20db/dec,通过=1点的直线 C、负20db/dec,通过=0点的直线 D、20db/dec,通过=0点的直线 答案：A 第13题 线性系统和非线性系统的根本区别在于( )。 A、线性系统有外加输入，非线性系统无外加输入 B、线性系统无外加输入，非线性系统有外加输入 C、线性系统满足迭加原理，非线性系统不满足迭加原理 D、线性系统不满足迭加原理，非线性系统满足迭加原理 答案：C 第14题 根据输入量变化的规律分类，控制系统可分为( )。 A、恒值控制系统、随动控制系统和程序控制系统 B、反馈控制系统、前馈控制系统和前馈反馈复合控制系统 C、最优控制系统和模
5、糊控制系统 D、连续控制系统和离散控制系统 答案：A 第15题 设控制系统的开环传递函数为G(s)=10/（s+1)(s+2) ，该系统为( )。 A、0型系统 B、I型系统 C、II型系统 D、III型系统 答案：B 第16题 微分环节的频率特性相位移()=( )。 A、90 B、负90 C、0 D、负180 答案：A 第17题 积分环节的频率特性相位移()=( )。 A、90 B、负90 C、0 D、负180 答案：B 第18题 有一线性系统，其输入分别为u1(t)和u2(t)时，输出分别为y1(t)和y2(t)。当输入为a1u1(t)+a2u2(t)时(a1,a2为常数)，输出应为( )
6、。 A、a1y1(t)+y2(t) B、a1y1(t)+a2y2(t) C、a1y1(t)-a2y2(t) D、y1(t)+a2y2(t) 答案：B 第19题 I型系统开环对数幅频渐近特性的低频段斜率为( )。 A、负40(dB/dec) B、负20(dB/dec) C、0(dB/dec) D、20(dB/dec) 答案：B 第20题 比例环节的频率特性相位移()=( )。 A、90 B、负90 C、0 D、180 答案：C If we dont do that it will go on and go on. We have to stop it; we need the courage t
7、o do it.His comments came hours after Fifa vice-president Jeffrey Webb - also in London for the FAs celebrations - said he wanted to meet Ivory Coast international Toure to discuss his complaint.CSKA general director Roman Babaev says the matter has been exaggerated by the Ivorian and the British me
8、dia.Blatter, 77, said: It has been decided by the Fifa congress that it is a nonsense for racism to be dealt with with fines. You can always find money from somebody to pay them.It is a nonsense to have matches played without spectators because it is against the spirit of football and against the vi
9、siting team. It is all nonsense.We can do something better to fight racism and discrimination.This is one of the villains we have today in our game. But it is only with harsh sanctions that racism and discrimination can be washed out of football.The (lack of) air up there Watch mCayman Islands-based
10、 Webb, the head of Fifas anti-racism taskforce, is in London for the Football Associations 150th anniversary celebrations and will attend Citys Premier League match at Chelsea on Sunday.I am going to be at the match tomorrow and I have asked to meet Yaya Toure, he told BBC Sport.For me its about how
11、 he felt and I would like to speak to him first to find out what his experience was.Uefa hasopened disciplinary proceedings against CSKAfor the racist behaviour of their fans duringCitys 2-1 win.Michel Platini, president of European footballs governing body, has also ordered an immediate investigati
12、on into the referees actions.CSKA said they were surprised and disappointed by Toures complaint. In a statement the Russian side added: We found no racist insults from fans of CSKA.Baumgartner the disappointing news: Mission aborted.The supersonic descent could happen as early as Sunda.The weather p
13、lays an important role in this mission. Starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-
14、to-day weather lives. It will climb higher than the tip of Mount Everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause),e can expect a
15、 lot of turbulence.The balloon will slowly drift to the edge of space at 120,000 feet ( Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform.Below, the Earth becomes the concrete bottom of a swimming pool that he wants to land on, but not too hard. Still
16、, hell be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. It will be like he is diving into the shallow end.Skydiver preps for the big jumpWhen he jumps, he is expected to reach the speed of sound - 690 mph (1,110 kph) - in less than 40 seconds. Like
17、hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him completely.If he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. His team hopes its not need
18、ed. Instead, he plans to deploy his 270-square-foot (25-square-meter) main chute at an altitude of around 5,000 feet (1,524 meters).In order to deploy this chute successfully, he will have to slow to 172 mph (277 kph). He will have a reserve parachute that will open automatically if he loses consciousness at mach speeds.Even if everything goes as planned, it wont. Baumgartner still will free fall at a speed that would cause you and me to pass out, and no parachute is guaranteed to work higher than 25,000 feet (7,620 meters).cause there
