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[APPLAUSE] MODERATOR: today our keynote speaker is Tom Friedman. I have a story Tom doesn't know. I first heard him speak at a graduation ceremony. I think it was his daughter and my son were classmates. And it was the graduation ceremony at Yale. And I recall him giving the graduation speech. And it was truly a tour de force of both deep insight and personal commentary about their futures. It occurred to me then, my universal answer to the question when you're in a meeting and you are planning an event, well, who should we get to come speak? It made it real simple. I just kept saying. Thomas Friedman. And I continued to do that for several years in a row. And guess what? We finally got it to work. So it's my honor to introduce Tom Friedman, who actually needs very little in the way of introduction. But, being polite, I will give you some of the highlights of what's an extraordinary career. He is one of the keenest observers and commentators on the issues ...

[Music] oh [Applause] [Music] [Applause] [Music] hi last time we had looked at an introduction to compensation of feedback systems in other words how do we modify Loop transmission of a feedback system in order to improve its performance possibly increase its speed of response or increase sensitivity improve the stability of the system those sorts of modifications that we very frequently want to make to to feedback systems the simplest kind of modification we can make is to change the low frequency magnitude of the loop Transmission in the notation we've been using the a fnot product and we've looked at how that influences the root Locust diagram for example and and last time looked at how that might improve the stability of the system today I'd like to look at somewhat more complicated modifications of the loop Transmission in particular ones that change the Dynamics associated with the loop transmission the simplest thing that we can do is to add a dominant ...

[Music] oh [Applause] [Music] [Applause] [Music] hi today I'd like to look at the stability problem in a somewhat different way we've found to this point that we have two methods for evaluating the stability of a feedback system one of them we looked at very briefly or principally via homework problems in particular the rowth test and what the Ralph test does is simply give us a a straightforward numerical way of determining the number of poles of a closed loop transfer function that lie on the right half of the S plane hi today I'd like to look at the stability problem in a somewhat different way we've found to this point that we have two methods for evaluating the stability of a feedback system one of them we looked at very briefly or principally via homework problems in particular the rowth test and what the rowth test does is simply give us a a straightforward numerical way of determining the number of poles of a closed loop transfer function that lie ...