Why Statistical Mechanics? Understand predict the physical properties of macroscopic systems from the properties of their constituents Deterministic approach ma F need of 6n coordinates at t: r: and v but typically n= moles (1023)! Ensemble?rather than microscopic detail and its surroundings microcanonical, canonical, grand canonical

一、已知无源二端网络ab端电压u=50√2cos(103t+10°)V 电流i=5√2cos(103t-26.9°)A a i 则网络的输入阻抗Z=8+j6 输入导纳y=0.08j0.06S

4高阶导数 一、高阶导数的概念: 加速度a(t)=v=高阶导数

1阶的概念 设x→x0时(x),y(x)都是无穷小量。 1)若lim(x)=1,则记0(x)w(x)(x→x)。称之为等价无穷小 i)若m2(x)=0,则记(x)=(x)(x→x)。称o(x)是比v(x)的高阶

uniT 8 The Development of Paging System means[mi:nz]n.方法,手段,工具 advantage[ad'wa:nti]n.优势,利益 availability[a' veila' b i t i]n.可用性,可得性 assume[a'sju:m]v.假定,设想 dramatic[dra' mae t i k]a.戏剧的,鲜明的