作为世界四大快递巨头,自2004年开始特许加盟--发展,共同经营快递业务,tT 目标是在年底发展伙伴50家,据权威机构预测:到2010年中国将成为世界第六大快递市 场。TNT在英国特许加盟已经有20年的历史中国是继英国之后在全球开展这种运营方 式的第二个国家

Handout 2: Gain and Phase margins Eric Feron Feb6,2004 Nyquist plots and Cauchy's principle Let H(s) be a transfer function. eg H(s)= s2+s+1 (s+1)(s+3) Evaluate H on a contour in the s-plane. (your plots here)

Handout 6: Proportional Compensation Eric Feron Feb25,2004 Plant under study: 1/10 G(s)=(s+1)(s/10+1)2 Compensation Scheme: We adjust the gain K in the feedback loop (draw the feedback loop below)

Handout 4: Root-Locus Review Eric Feron Feb17,2004 Summary of Guidelines for plotting a root-locus 1. Mark Poles X and Zeros O 2. Draw the locus on the real axis to the left of an odd number of real poles plus zeros

Handout 8: Lead compensation Eric Feron March 3, 2004 Lead Compensation goals: Raise phase (and gain) at high frequen- cies while not touching low-frequency system's characteristics: Can extend bandwidth of system Canonical lead element:

Handout 10: Notch compensation Eric Feron March 8, 2004 Notch Compensation goals: Kill nasty frequencies (eg resonant fre- quencies). Canonical Notch element:

Handout 16: Describing functions, More Eric Feron April 7, 2004 Continuing on the switch nonlinearity

Handout 15: Describing functions, Introduction Eric Feron March 31, 2004 General Philosophy General reponse of arbitrary nonlinear systems is somewhat complicated. We usually know the systems we work with. Work with finite families of 'most likely

Handout 14: Introduction to nonlinear systesm Eric Feron Mar29,2004 Linear systems reminder:

“由于美元持续贬值,以与美元比价为准的人民币实际汇率也持续下降。”宋国青表 示。 据测算,从2002年2月到2004年1月,美元相对于其他主要货币的名义有效汇率已 下跌了25%左右。然而,由于美国严重的财政与贸易双赤字局面短期内无法改善,很多国 际专家认为美元贬值的局面目前仍难以扭转