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Missile Defense

Technology has always found its greatest consumer in a nation's war and defense efforts. Since the last attempts at a "Star Wars" defense system, has technology changed considerably enough to make the latest Missile Defense initiatives more successful? Can such an application of science be successful? Is a militarized space inevitable, necessary or impossible?

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rshow55 - 08:27am Jan 22, 2003 EST (# 7896 of 7899)
Can we do a better job of finding truth? YES. Click "rshow55" for some things Lchic and I have done and worked for on this thread.

Gisterme raised some points about oscillations, and how engineers strive to get rid of them in control systems - as they have since the 1940's. I've made the point that oscillatory solutions - where there are alternating adjustments - alternating points of view - conflicts - contradictions - and yet good adjustment and stability. The Bush administration, and the US military-industrial complex of interlocking, crosstalking, mutually reinforcing organizations are continuing to have fundamental problems that were of deep concern to the leaders of the US military-industrial-intelligence affairs from 1942 on - that is, since it became clear that control stability was an intractable problem. I'm quoting from Analysis of Nonlinear Control Systems by Dunstan Graham and Duane McRuer 1961 - Dover ed 1971 (I wore out my original edition - and am transcribing from the Dover edition.) This is a book I was given to read, and did read, in preparation to meeting Wolfgang Flugge, of Stanford, who had agreed to assist in my instruction, so far as engineering mechancs went, if I satisfied him with my mastery of this book. (I did, but Flugge told me I had only done so by the skin of my teeth. He was, however, willing to do me the great favor of flogging me into near-presentable shape - something he later told me he thought some of his associates and he had barely done. )

Chapter 10 - Epilog and Consequence

"Early investigators of feedback control systems, such as Minorsky (1922) and Hazen (1934) pointed out and treated important nonlinear characteristics. but in the explosive expansion of control system technology which followed the introduction of feedback amplifier design, attention was concentrated almost exclusively on linear systems for more than a decade (refs from 1932-47). During this time the analysis of nonlinear systems was often considered to be inordinately arcane, at least in the United States. Two survey papers which approximately bracket this period and which reflect the then-current view are the ones by Von Karman and by Bennet. The appearence of the comprehensive book by Minorsky, of hte english language editions of the source books by Kryloff and Bogoliuboff and by Andronow and Chaikin, and the papers by Goldfarb stimulated renewed interest in the problems of nonlinear control systems, ans showed the paths which have been followed since. (This statement, however, is not to be construed to say that there were not numerous other significant contributions to the theory of nonlinear mechanics and its applications. Every investigation of nonlinear control systems is, in fact, founded on the results of investigations in other branches of mathematics and mechanics. Very extensive historical bibliographies have been given by Higgens and by Ku.) The points is that the engineering literature on the subject of nonlinear feedback control systems is practically nonexistent for any year prior to 1950. Beginning in that year, there have been a continually increasing number of reports, papers, and books on the subject of this book.

"In spite of the many words which have been used her to elaborate the discussion, and perhaps to hide the fundamental fact, both the study and the physical synthesis of nonlinear control systems are, still today, in a somewhat unsatisfactory state.

" The multidudinous methods of mathematical analysis are amenable to particular problems, and there is no workable general theory. Of course, a solution to any given linear equation with given specific conditions or forcing functions may be easily and rapidly found by machine methods, and both analog and digital computers are common fixtures in industrial research and design departments, as well as in engineering schools. Where computing machinery is not available, step by step numerical or graphical methods may be applied by human computers to find one or more solutions. Eve

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