We haven’t been able to find out the()of the rumour.
A.source
B.cause
C.origin
D.reason
A.source
B.cause
C.origin
D.reason
Zhongxing Chemicals Corporation in China exported two tons of disinfectant (消毒剂) in one container to the United States. The trade was effected on the term of CIF New York US$ 20000. Upon the reception of the consignment at New York Port, the Consignee found the disinfectant was wet and useless according to the normal function of the substance. The consignee brought the claim against the Carrier and Insurer and gave the notice to the local survey agent mentioned in the Policy without any delay. The cause and origin of the damage, in accordance with the survey report, is the moisture in the Container, resulting either from: Stuffing of the goods in an atmosphere with a high hygrometry (湿度) Accidental wetting by rainwater during the course of stuffing Stowing the bags on wet wooden bases.Questions:(可用中文回答)(1)What shall we do according to the survey report?(2) If the shipper presented a loading inspection report as follows, what measures shall we take?
(1)求曲线在点(x(t),y(t))处的切线L(t)的方程;
(2)证明L(t)在坐标轴上的截距平方和等于a2.
已知向量组1=(0,1,-1)T,2=(a,2,1)T,3=(1,1,0)与向量组a1=(1,2,-3)T,a2=(3,0,1)T,a3=(9,6,-7)T具有相同的秩,且3能由a1、a2、a3线性表示,求a,b的值。
设f(x)是以T(T>0)为周期的连续函数,且满足证明f(x)的原函数也是以T为周期的函数。
A.当θ/ω>1时,y(t)与P(t)同向,当θ/ω<1时,y(t)与p(t)反向
B.当θ/ω>1时,y(t)与P(t)反向,当θ/ω<1时,y(t)与P(t)同向
C.不论θ/ω如何,y(t)与P(t)同向
D.不论θ/ω如何,y(t)与P(t)反向
一单位反馈控制系统的开环传递函数为
已知系统的x(t)=1(t),误差时间函数为e(t)=1.4e1.07t-0.4-3.73,求系统的阻尼比ζ、自然振荡角频ω0率 、系统的开环传递函数和闭环传递函数、系统的稳态误差。
已知单位负反馈系统的开环传递函数为:
其中K>0、T>0。试确定使闭环系统稳定时,参数K、T应满足的关系:并计算在输入r(t)=tX1(t)作用下系统的稳态误差。
构造有限状态机M=(Q,S,R,f,g,q1),其中,S=R={0,1,2,3}.对于t>2有r(t)=m(t)+n(t),这里如果s(-1)=s(0)=0,确定r(1)和r(2)。
已知单位负反馈系统开环传递函数
试分别求出当r(t)=1(t)、t和t2时,系统的稳态误差(e=r-c)。
设函数f(u)连续且恒大于零,
其中Ω(t)为球体(x2+y2+z2≤t2),D(t)为圆域(x2+y2≤t2).
(I)讨论F(t)在区间(0,+∞)内的单调性;(II)证明当t>0时,