2.1已知R1=R2=102U=2V,当t=0时开关闭合求(0)i2(0)i(0+)u1(0) 2.2已知Us=10VR1=10QR2=5Q,开关闭合前电容电压为零,求开关闭合后i(0)

Statistical approach to estimation Examine the multivariate Gaussian distribution: (x-)\v-(x-) Multivariant f(x)= Minimize (x-u)'v(x-u) gives largest probability density By minimizing the argument of the exponential in the probability density function, we maximize the likelihood of the estimates(MLE)

1.态的表象 在量子力学中,描写量子态和力学量的方式不是唯一的。一种具体的方式称为一种表象。我们在前 面已经介绍过坐标表象和动量表象。在一维情况下,(x,t)描写量子态是坐标表象,用中(pt描写 量子态是动量表象,它们之间是 Fourier变换的关系。这两种表象都是连续表象。 现在介绍一般的离散表象。取一个力学量(算符),假设它的本征值集是离散的,记为 {q1,92,},本征函数系记为{u(x)u2(x)…}。为简单起见,先设所有的本征值都是非简并的

Part I Structure and Vocabulary Section A on A Directions: Beneath each of the following sentences, there are four choices marked A, B, C and D. Choose the one that best completes the sentence. Mark your answer on the ANSWER SHEET. (5 points) ome to study in the U.S., by thhright scholarships, oth the U. S. government's Agency for International Development, by the Ford Foundation, and so on

下面分析二种典型的固结不排水试验应力路径 (1) 常规三轴试验应力路径，先在均匀压力下固结此点，然后保持3不变，不排水下增加1至破坏，TSP线为与横轴成４５°斜线，若此时孔隙水应力为u,量得CB= u ,连接AC 点得ESP线

Goals Theory A priori A priori error estimates N1 bound various“ measures” of u exact]-un [approximate] in terms of C(n, problem parameters h [mesh diameter, and u

())/0=),6()/+2g= edrhugdr)/2M),oxdx) o: Elex Enwk'< uz=x), a(z qurgdiea= uuv y= adwvopu)z(o j): ac=2 Ghwceo(udo: 2M( Hw(uy 0: w cloks rE o Chu Tnr(i b)iwgiffadu cu wa rdo h ouno pk- which wite pexy a ca)=dre halfan a)+x=gub)whwxppdpxiv z=ioy u)udre Wwv ay co)(igad )o)a)i o u v( wh

费马定理设函数f(x)在x的某邻域U(xo)上有定义, 并且在点x处可导,如果对任意x∈U(xo) 有f(x)≤f(xd),或f(x)f(xo 即在x取到极值,则f'(xo)=0 证明:不失一般性。设f(x)在点x=c取到最大值, 则f(x)≤f(c),x∈(a,b)

1.分波法的一般公式 现在假设势场为中心势场V=(r),那么方程就变为 v2y+[k2-u(r)y=0.u(r)=v(r) 显然,这时f(0,)变成了f(0),(r,0,)变成了(r,0),而且2是守恒量,所以不妨假设

确定局部损失系数的实验方法 例用U形压差计测量水平放置弯管的局部损 失系数。已知d=0.25m,Q=0.04m3/s,U 形管工作液体的密度P=1600kg/m3。如果 测得△h=70mm,试计算5 解忽略沿程损失,对1和2断面列出伯努利方程