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Missile Defense

Russian military leaders have expressed concern about US plans for a national missile defense system. Will defense technology be limited by possibilities for a strategic imbalance? Is this just SDI all over again?

lunarchick - 07:57am Mar 19, 2001 EST (#1162 of 1166)
lunarchick@www.com

http://www.newscientist.com/dailynews/news.jsp?id=ns9999514

rshowalter - 09:16am Mar 19, 2001 EST (#1163 of 1166)
Robert Showalter showalte@macc.wisc.edu

almarst-2001 – On your question “why so little interest and participation in this seemingly important forum” ----- I believe there is more interest than might at first appear, and have reasons to believe so. But on the question “why so little participation” the answer, in large part, is fear. I can discuss that, in better detail, after setting out a specific example that is interesting, that can be checked, and that has things in it that may be helpful in understanding current problems -- including those where the word “misunderstanding” may be neutrally used, and circumstances where moral issues also arise. For judging what is misunderstanding, and what is fraud, usefully and in context, one needs to know some detailed things about how the human systems involved work.

Steve Kline led the fight, over fourteen years time, that eventually supplanted one paradigm in fluid mechanics with another. It was, in detail, a bloody business, showing almost all the ugly aspects of the interaction between Russia and the United States, played on the much smaller, nonlethal stage of academe. I wish Russian historians, or scholars, could understand in detail the “behind the scenes” interactions that actually occurred, in this specific case, or some other specific case, and did so in detail. If they did so in detail, they’d see similarities between American and Russian usages, but would also see patterns of cooperation and coercion enormously different from their own. If they understood the pattenrs, they’d not wish to imitate them in Russia –and in many ways, could not do so, because the cultures, each very valuable, are nonetheless very different. But they’d be able to interface with American usages more effectively, and be better able to judge notions of “bad faith” and “good faith” with more reliability and sophistication.

(I’m personally engaged in another paradigm conflict, now in the process of resolution, that would, if examined, also show many things that Russians need to know, and I feel do not know, about how American sociotechnical systems work, and how both efficient and bad decision making occurs in them. I believe that, for resolving matters of peace and war, this knowledge may be essential.)

rshowalter - 09:17am Mar 19, 2001 EST (#1164 of 1166)
Robert Showalter showalte@macc.wisc.edu

Here are excerpts from Self-Sustaining Mechanisms of Wall Turbulence

Chapter 1: A brief History of Boundary Layer Structure Research -- S.J. Kline – Department of Mechanical Engineering, Stanford University, Stanford Ca 94305_3030

Abstract:

"The origins of boundary layer structure research are set into the context of turbulence research as a whole. Turbulence research is seen as consisting of four eras: (i) Mean flow; (ii) Statistical; (iii) Structure and Differential Equation Modeling; (iv) CFD (computational fluid dynamics). The shifts from one era to another are tied in each case to the creation of new instrumental methods. Structure research began at the start of the third era, during the 1950’s, and involved a paradigm shift. The paper includes remarks on the nature of paradigm shifts and the resolution of conflicts in research as a means of thinking about the future.

1. Introduction: "Boundary layer structure research in this paper is taken to by synonymous with the physics of how turbulence is produced and maintained near solid boundaries. Three distinct strands of work, all arising in the 1950’s, led to continuing research in boundary layer structure: (the conceptual work of Theodorsen (1952); (ii) the study and extrapolation of corellation data by Townsend (1956), and the flow visualization work of the author and his colleagues at Stanford (Kline and Runstadtler, 1959, Runstatler et al, 1963, Scharub et al, 1965; Kline et al, i967 ). In order to undersand how and why these strands of research arose, it will be helpful to review the history of turbulence research as a whole.

"I will, somewhat arbitrarily, describe turbulence research as occurring in four eras. Since this review is intended to provide an easily understood overview, it purposefully omits many details. Nevertheless, the omissions are not the dessiderataa; indeed they may be undesirable. Nevertheless the omissions are a ncessity if we are to understand the overview owing to the limitations of the human mind. The most important single limitation of the human mind for turbulence research is our inability to hold more than 7 (plus or minus 2) bits of uncorrellated information in our short term (working memory) – the thinking part of the brain. This prevents us from holding in mind all the details of turbulent flow. We must reduce the data to a simpler picture for understanding. This carries the hazards that we will create oversimplifications, and also that different workers will arrive at conflicting models. Both have happened in the boundary-layer problem and there is, consequently, a need to reconcile the various results. . . . .

From 4.1 “By the late 1950’s several kinds of data had accumulated that were contradictory to the picture of boundary layer turbulence as a random statistical set of fluctuations for the layers outside what was still called the laminar sublayer …….

“Repeated attempts using many kinds of theories to utilize statistical theories for calculating turbulent flows were unsuccessful. As H.W.Liepmann in one of his periodic reviews of the field of turbulence remarked, “Turbulence is the graveyard of theories.”

. . . . .

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