[FRIAM] kathy.saunders
How is it going? http://www.maricom.pl/mmoe.php?oluxidname=83 Sat, 28 Jan 2012 17:49:39 __ "I wish you would go away." (c) BERTRAM waehlerischesten FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] The Primacy of Primeness!
Prime Theory -- not to be Mocked, or Knocked! My tutor in grad school math at Cambridge was one Shaun Wylie, dead now; a famoso number expert. He was a supervisor at Bletchley where a chappie called Turing worked for him. They broke ENIGMA, that may have won the war -- certainly shortened it by a year or so. Interestingly, the Krauts were so convinced of their profs' bloody brilliance that for years they refused to believe that some bloody non-Aryan Limeys coulda broken it. Thus giving us lotsa running room! Being a young ignorant prick (now, regrettably, an Old IP), I made stupid jokes like that the number one to the nth power had n divisors. With his modest integrity, he quietly filled me in on some of the practical uses of prime theory for code breaking. And he NEVER just talked about math -- he DID things with it!! There is indeed " more in heaven and earth, Horatio, than thy philosophy dreams of". Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] On being the Right Size
I have read the postings on animal size and characteristics. I woulda thought that canine counter-example demolished the heart beat hypothesis. Didn't Sherlock Holmes comment on "the strange behavior of the dog"? Some personal experiences are of interest. In 1976 Paul MacCready and I started looking at a human powered flyer. I was responsible for lift and propulsion and studied same. Not having the luxury of Friam correspondents, for whom talk is all, I needed to know the correct results, and incorporate them properly. There's a lotta data on human power, much from cycle-type ergometers. Conclusions are that, roughly speaking, legs, arms, torso, together or separately, put out about the same amount, and, within reasonable frequency ranges, the power is invariant with rate. Thass why gears on bikes is so good! Human bod a pretty fine machine! This was helpful, since I could design a prop of size and speed that the air liked, and assume our excellent pilot/engine, Bryan Allen, would be able to harness it with his usual consummate style and skill -- and fly! He did! On the effect of scale, the general result is that smaller animals have a higher power/weight. For example, Mickey (Mus musculis) can do more at his weight than Dumbo (Loxodonta africana). My scaling calculations indicate that the human being is indeed the largest of the animals capable of flight. Many folks find this touching! The Bard did. " Oh what a piece of work is a man! How noble in reason! How infinite in faculty! In form, in moving, how express and admirable! In action, how like an angel! In apprehension, how like a god!' Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Unmanned Weapon Systems
This is indeed an interesting subject. Since David with his sling, humankind has been fascinated with Action at a Distance. Makes perfect sense to me. I see no moral distinction between removing an evil person with ground boots, artillery, manned or unmanned air strikes. But huge convenience and safety in the last. I wish, apropos the appropriate treatment of Bin Laden, someone had invoked that ancient prayer: "Deliver us from Evil". Wasn't there a cat, name of Jesus, actually said we should pray for that. He was a pretty good guy, in spite of some of his current followers here. In my latter days at AeroVironment (AV) we became interested in ornifloppers, starting with the Quetzalcoatlus Northropi, now in the Smithsonian. It flew f'n feebly. Authentic, perhaps! At the time I thought a basic, fundamental, theoretical study would be needed to start design. It's a hellish tricky business: unsteady, large amplitude, separated, viscous, vortical flow. Ask any birdy! I proposed first we'd try to solve the simplest case, "steady" level flight, and go from there, followed by designed envelope-pushing flight test, a la grown-up aircraft. It's impossible to do correctly on computers, anyhow. As usual, I was completely wrong, and freely admitted it, unlike some Friamers! Discussed this at length with Paul MacCready, and we decided, "Baby birds, fledgelings, they dunno flight theory or control circuits; they jus' flaps around, learning as they flop along". So Machine Learning was tried. Worked beautifully The latest AV UAV, Hummingbird, is a true marvel. It was developed sans specific theory, save deep and wise aerodynamic knowledge, but designed with full wing articulation and plenty power, plus actuators, servos and gyros. Then taught to fly. Fly, crash, change gains, fly, crash, etc, and finally fly -- fly away, birdy! That little 14 gm miracle, flies forwards, backwards, sideways, up, down and no where (hover). With on-board TV, Nature's version (about the same weight) no got that! Interestingly, the flapping lift system is not biomimetic for its own sake, but because it permits: zero flight speed and weird maneuvers, banging into things without breaking airframe stuff, and, obviously, superb camouflage. You can look it up, amigo. Uno milagro! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Numeracy!
I taught at the Art and Design Center in Pasadena for twenty years - a range of subjects from automotive design to Renaissance technology. My students, very talented young women and men, gave you the Miata and the new VW Bug. We staff were troubled by the students' trouble with numbers. I noted at a faculty meeting that "literacy" meant you could write or read: a love letter, a legal document or an instruction manual, without knowing who Shakespeare was, or how to parse a sentence; so, in the same spirit, " numeracy" was needed. I was given the task of designing a new course, teaching "numeracy", and did. It worked fairly well. For example, new students, having passed high school algebra and able to solve quadratics by rote, could not calculate how many square feet of carpet was needed for an irregular apartment floor, and worse, foot run if the carpet came in rolls X feet wide, and worser still, if the carpet roll was patterned! After my class they could! Just what designers needed! We developed a text, printed at the school, and a number of procedures, many graphical, that worked pretty well. Yuss, mathematics is too important to leave to mathematicians, speaking as a Caltech Ph.D. in that arcane discipline. I happen to have a strong aversion to the usage of "intuition", since I think it means nothing, except when one has some empirical experience of the subject, when it becomes "judgment". Other artistic usages are nuttin' but Voo Doo! Fer example, when I have seen its airlines and the stability derivatives I have pretty good "intuition" of how an aircraft will perform in the lateral mode, and my test pilot "intuits" the same thing from turns, spirals and spins in flight. Any thing else is BS! Be glad to discuss if anyone is doing something in the same spirit. As I have promised, everything discussed here is from direct experience. I don't have enuff imagination to speculate, or intuit!! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Slinky Solutions!
Yes, the postings apropos Slinky all delightful, but "information" -- no, no, gimme a break. I'll bet the "information experts" doan have a clue how to solve! Newton (fl. 1680) could readily have solved, as could Joseph Louis Lagrange (fl. 1800) and those estimable gents never hearda "information". Easy to write the equations of motion for a discrete no. of elements and solve , or, if you have the courage, write the continuum equation in space-time and solve using the Lagrangian and Runge-Kutta IV. It's only second order! THEN, insert proper constants for geometry, density and compliance and obtain NUMERICAL values for the solution. Then, and only then, you unnerstan and can discuss same. As for unexpected behavior, follow Feynman's dictum, "Don't "explain" physical or mental behavior until you actually know what it was. Then tell folks why it happened"!! One interesting thing about slow, slinky-ish bodies is that there is minuscule damping; coefft. of restitution of steel above 95%, and precious little air damping, so they seem to go on forever. Great model for a non-dissipative system. I spent fair, and fun, time with those thingies. I dunno why children like Slinky. A funny business. Called market research. When I consulted for Mattel, we tried children on toy ornifloppers that flip-fla pped across a room floating o n the air -- ornithic and angelic! But the kids preferred little horsies with wooden wheels. We adults thought the flyers were stunning, but to a kid, everything is AMAZING . What a Wonderful World! And how soon some of us leave it! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Space-Time Issues
My superficial knowledge of the subject comes from an A in a grad class at Caltech on Relativity, long before GPS. No problem in measuring interval between events at the same place, with a relativistic correction. The issue here is synchronization of clocks at different points in space (CERN and Italy). This is doable, of course, but not trivial. Still hopin' Mr. Natural will enlighten me! Incidentally, most "explanations" of GPS are vaguely incorrect. You CAN'T directly measure the time a signal takes to get to you, sitting at a mountain lake, from a Teapot in the sky, because you can't synchronize your $199 Gelsons GPS unit. It doan really know when the signal was sent. There's a tricky little calculation involving the difference in arrival time at your station between calibrated signals from two located, synchronized Teapots. It does assume you are at one place at a given instant -- oftentimes the case with me. GPS, like most things in this world, is much smarter than its interpreters! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Ignorant, Again!
Can someone tell me, in my doomed ignorance, how they timed that too-speedy particle arriving at CERN? I know it's elementary for those to whom it is. Mebbe Bruce Sherwood can give a briefing? I welcome. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Sense and Sensibilty
Elementary, my dear Dr. Holmes! I totally concur with his views that most Big decisions in life are in the province of philosophy and humanity, not physics. For an Oxford mathematician he shows surprisingly good sense! We have many ethical decisions -- who: to marry, to make war on, to provide health for (or not), to execute, to incarcerate, to educate, to abort, or to tax. It’s all about People. Dear, delicate, indestructible, warm, foolish, fallible, infuriating people! Oh Yes, what a piece of work is a Man, in form and moving, how like an Angel, in apprehension how like a God! These ethical decisions cannot be made by physicists (who really execute very little, and that, often foolishly) and God forefend that they should be made by God’s People. Enter the Philosopher. As a simple mechanic, ignorant of 99.9% of the World’s Wisdom, I am grateful for, and guided by, the thoughts of philosophers on these issues. We are indeed fortunate to have artists, philosophers and physicists. But, but, but, Friamers would do well to remember that C omputation teaches neither A rt, nor P hilosophy, nor P hysics. I habitually started my classes with Picasso’s dictum, “Computers are useless; they only give answers”. It annoyed the students , so served some didactic purpose. My hope was that, in the discussion following , they might propose that what Pablo " might of meant" was that questions are more important than answers. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] A Pretty Wet Explanation
Take a circular cylindrical container with a small, short bell-mouthed orifice in the base center. Now fill it and remove the stopper. As John Falstaff would have it, “Broach that bloody keg!” What happens? The water comes out the bottom – if I can be forgiven some complex technical verbiage! It does, indeed, and runs out the orifice in an approximately uniform flow, at a speed related to the height of the free surface above the outlet, the square root, to be precise. This was predicted by Galileo and has been supported by hundreds of 1,000s of experiments, including my own, conducted in steamy, malarial Kwa Zulu Natal, in the 40s one of the Last Outposts of the Empire. Our hydro lab instructor was a cultured, gentle Professore Italiano, washed ashore on the southern tip of this rough continent by the tides of the recent war. He told us, an unruly bunch of ranchers’ sons, that we should heed his hydrodynamics, since his ancestors had designed the aqueducts of the Roman Empire . We were duly impressed. This was class, of which we had little. Our ancestors had mainly built railroads, dug gold, imbibed cheap liquor and shot the local fauna (and, sadly, sometimes the inhabitants, too). I enjoyed doing hydro experiments with water that, only a few weeks ago, in its younger life, had harbored crocodiles and hippopotami. I don’t suppose too many of my fellow engineers thought like that. And I owe Dottore Luigi much for introducing me to the fountain designers of the Renaissance, maestros like Nicola Salvi who did the Fontana di Trevi. Hydraulics engineers calculate this outflow using a “constant” called the orifice coefficient, a function of the nozzle shapes involved. It’s tabulated in handbooks, and seldom less than 90%, so is hardly observable by jes lookin’. The orifice always seems to run full. One can also calculate the entire flow in the container, assuming there is not much dissipation, as is normally the case. Enter Signore Bernoulli, as the conservation of potential, kinetic and pressure energy. There is a lovely expression, called the Stokes Stream Function, that defines stream tubes within the container. These stream tubes have the shape similar to the outer container for the large radius flow, and, near the axis, smooth the kinks out to be roughly cylindrical. Particles cannot move from one stream tube to another, so that the velocity can be calculated. There is no problem in conceiving of the rules for this, but a computer is needed to take into account the details of the flow boundaries. Analytical functions particularly hate right angles, so tiresome computer calculations with teeny elements are required to nickel and dime the flow near the bottom corners. It the fluid is set into rotation by paddles (that, to minimize turbulence, should not be perforated) then a swirling flow is produced. There’s one in your car, called a fluid drive. Most of this rotary flow is irrotational, so the Laws of Bernoulli hold, roughly. But the energy of the flow is increased; you stirred it up, after all! The free surface, at constant pressure, has a dimpled depression near the axis. Its radius, r, and depth, h, satisfy the condition r 2 h equals constant, defining a kind of curved conical cavity like, and beautiful as, a Calla lily. Near the center, the depression gradient flattens out due to viscous effects that prohibit high central velocities, as would occur for the simple 1/r vortex flow model. The scale of this inner radius depends on the swirl rate and the kinematic viscosity of the fluid. It’s different for oil or water. Small, sticky flows, like filling your crankcase with oil, behave quite differently from vast, slick flows, as in the 500 km Florida Gyre of the Gulf Stream, on which I published in the grandiose, but doomed, Coriolis Project. If Bernoulli holds, then the speed of the outlet flow still obeys that Law. This implies that the exit speed is always higher than that of the non-swirling flow. But the angular momentum is conserved, so the direction of the flow is no longer vertical. The rate of flux out of the container is reduced by this angle. The question is whether the increased speed is offset by the increased inclination. You just gotta crunch the numbers to see what wins, and construct a flow model – inviscid is not too bad, laminar can be treated numerically with Navier-Stokes, but turbulence; “Oh, My!”, as Dick Feynman was wont to say. I think that the results are that introducing swirl has a bimodal effect. This world is neither monotonous nor monotonic! Sometimes swirl increases the outflow, sometimes not. I tried to express this in the Karman parable about the Prof who could explain anything, once he knew the result. Evidently this is a fertile field for inspired interpretation. Voodoo artistes l
[FRIAM] A Most Ingenious Paradox
Yeah, name-dropping, I know, but the truth. I actually discussed that fluid mechanics puzzle with Dick Feynman, in the nude, in a hot tub! How could one be more open? It was about a “reversal paradox”, where you pump fluid down a swirl pipe one way and a rotor turns, but when you reverse the flow direction the rotation does not. I was able to correct Dick on the subject, simply because I had actually needed the answer for a wind turbine, thunk a gedanken experiment and then validated the conclusions theoretically. (Yuss, Newton appeared, but not in the tub!) Dick, a very open-minded guy, agreed, was delighted to be corrected and then proceeded to make advances at my wife, which was about par for an evening in leafy Pasadena in those days. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] A Malarial Brain
Friend pulsed me off-line. "Wot the hell you know about malaria? Somewhat over the Top, mon frere!" I wuz stung! I have promised that ALL my postings will be of real events that I have experienced or witnessed, so in defense, I note that I indeed contracted malaria as a child in Africa. It was a thoroughly disagreeable experience, but I recovered without too much mental warpage, far as I can tell. Incidentally, there is no cure and the disease, a faithful lover, is yours forever. This obliges me to consume copious draughts of gin and quinine tonic for medicinal reasons - a regimen that I observe with resigned dedication. There are relapses, sometimes caused by exhaustion from hard work, that I avoid by being a lazy slob, and sometimes caused by exasperation of the P lethora of Fools. That irritant I have not yet solved. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Experiment and Interpretation
Klowns like me are often misinterpreted, as noted by Yorick. I am ardently in favor of experiment, carefully observed. It is the basis of all science. But, but, the interpretation of observed phenomena must also be dealt with carefully. Voodoo has a pernicious way of creeping in. After all, for two thousand years we knew that malaria was caused by the bad air of the low, swampy places where it was prevalent, and deadly. It was only in 1896, after the Anopheles mosquitoes started reading the Annals of Tropical Medicine in the Lancet (not by a Limey, but Dr. Ronald Ross, an admirable Scots physician) that the little critters realized that they had the God-given gift of spreading the disease by biting white people, and thus helped the indigenous populations by keeping Europeans out of the “White Man’s Grave”. I love observations, and it is not for me to challenge what people see. If pious folks observe the image of the Virgin Mary on a half-baked tortilla, I say, “Let it be”. She certainly has Power to do that, according to Those in the Know, and it seems to me like a folksy, open-hearted gesture on Her Part, that our president would do well to emulate. But, a little learning is a dangerous thing, and it is injudicious to draw conclusions from phenomena that one does not understand the physics of. It is certainly valid for an honest amateur to ask, “But how can I know if my theory is Voodoo?” Here are some modest proposals: first, study as much as you can about the subject, second, understand it well enough to use the professional technical terms of the discipline and then, third, ask a few knowledgeable folks privately for their opinions. So, follows some constructive suggestions. Read. Learn. The Picasso of irrotational rotating viscous/inviscid flows was an amiable Top Brit, Sir Geoffrey Ingram Taylor. He is probably now sitting on some Tiepolo cloud up there watching with satisfaction the grand swirling vortical structure of the firmament of the heavens. I knew him as a lofty figure, and was honored to present the G I Taylor Memorial Lecture at a university far from here some 20 years ago. There is lotsa stuff on GI on the internet that one can read and learn from – in particular the Taylor-Proudman theorem that has a special charm for me, since before his name was immortalized, I was a lowly scholar in Dr. Proudman’s grad. fluid mechanics classes at Cambridge . He would not remember, but I recall him, as I melted silently, respectfully, into the woodwork of those 17 th century desks. Fer Gawd’s Sake, Newton sat right there! I held my peace. Dumb questions (which were all I could muster then, and even now) were not encouraged in the Old Maths Schools at the University. As for asking folks, it is my modest guess that, for all their many fine qualities, not too many Friam correspondents have that much background in the very esoteric, and charmingly pointless, subject of pouring fluids outa bottles – unless they be of a good vintage. But I will answer privately things that folk may ask personally, to the extent I am capable. It is nice, and generous, for the blind to lead the blind, but the truth is seldom approached by that sorta debate. It takes hard work, intelligence and the learning of new ideas. Incidentally, with reference to some discussions of high and low pressures at surfaces: ALL free surfaces for ANY fluid motion with stationary air as the contiguous external fluid are at the same CONSTANT pressure. How could they be otherwise? Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - - Original Message - FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] A Happy Thought (experiment)
I was amazed to learn that gedanken experiments involve so much depth. I had thought thought experiments were just simple tests that it would be VERY nice to do, but for various reasons could not be executed. Like having all gedanken foolosofers leap from high buildings (under humane and controlled conditions) and their trajectories measured to determine whether they obey the laws of gravity and Newton . Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] A Little Learning
Yes, correspondents are correct. My remarks were pretty stupid, as they usually are. Apologies. No one needs to be told what they don’t know. I was trying to make the point that in bathtub vortex flow there is huge body of theoretical and experimental research and probably no unk-unks, in the sense that there are no unknowns. We just can’t put ‘em all together. To be constructive, the issue can be idealized to a container with an exit orifice dispensing fluid in air. Jes holdin’ up a funnel in the breeze, M’am! If the losses are small the exit flow speed at the edge of the emitted jet is approximated by V*2 =2gh, independent of the fluid density, as was hypothesized by Leonardo (c. 1500), and well known to Galileo (c.1600), Newton (c.1700) and Bernoulli (1750). If swirl vanes are introduced, then the rate of outflow is reduced, since the vortical exit flow is inclined to the vertical. If you have a narrow, long, constricted nozzle, or filters, then, a’course, again outflow is reduced, and can be calculated if these impedances are defined . If it swirls of its own accord, then, unless tests show this to be equally distributed clockwise and anti, one must assume that one’s water or funnel is twisted or God is a casuistic Jester – both quite likely. Or that the earth is spinning, a modern hypothesis, denied by the Bible, but supported by my astronaut friends who claim to have actually observed same. As Nick notes, gedanken experimenten are a wonderful source of insight and “paradoxies”, and simple kitchen experiments for this case very productive. A’course, with real experiments, a lotta control issues go without saying, so I won’t. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Spin Doktors, and the Bathtub Vortex
The “Bathtub Vortex” has been much studied, by good hydrodynamicists and others, like me. It is a fine example of the Navier-Stokes Equations in their full glory, and can be solved (more or less) by techniques of Computational Fluid Dymanics (CFD). Turbulence, that often occurs, is dealt with, approximately, by Reynolds Averaging (RA) or Large Eddy Simulation (LES). Occasionally the theoretical solutions are supported by test. I have had humbling experiences trying to predict this flow for real aircraft vortex wakes and “validating” my results with flight tests on a B-707. Truth can be brutal! I would not venture into hand waving or word waffling on this topic. Friam folks may be entertained by Todor von Karman’s take. He relates that, in the waning days of the Austro-Hungarian Empire, the Viennese trolley cars had a passive ventilator on their roofs – a kind of funky S shaped impeller on a vertical axis that spun around in the breeze, and putatively sucked out the smoke from the professor’s cigars. The aero students asked their prof. to explain how it worked. He went into patient, painstaking detail with figures, equations and other Eulerian stratagems, finally deriving the sense in which it would rotate (but not the speed). The students then triumphantly noted, “But, Herr Professor, it goes the other way!” “Ah”, said the learned prof, “Zen I can explain zat, too!” I assume that aerodynamics is the same in Vienna as everywhere else, although we know, happily, the air itself isn’t. It is full of Arias, Bel Cante and Leit Motifs swirling, drifting in the breeze, that make Alt Wien truly the “City of any Dream”. If folks are interested in the “discovery” of the Karman Vortex Street , a classic phenomenon of unsymmetrical flow, I will be glad to post my article on this, as related by Todor himself, if someone can show me how to. On these subjects one resorts to a statement I’ve often made in expert witness work. “Theory crumbles before the Facts”. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Books, as Objects of Affection
The correspondence re e-books is indeed interesting. Starting as a grad student at Cambridge Univ., I made a vow to keep ALL books I had ever acquired (honestly or not). They were nice to have. And useful for many things. I enjoyed using the massive, tall Oxford English Dictionary as a stand for the chamberpot under my bed. We did not have bathrooms in our rooms in them days. So I inscribed each volume with my name, and place and date of acquisition. After half a centur y i t was comforting to look at those serried shelves, and feel that one understood, at least in a tiny part, the wisdom they contained. And to revisit, as with an old, valued friend. T hen, in 2002, the "Good Lord" chose to burn my house down, and my books. Along with 39 adjacent abodes. An admitted sinner, I wasn't too surprised, but never realized my neighbors were sinners, too. My wife said it was His way of telling me to retire, but I now think He was envious of my library . After all the Old Testament does say our Lord " is a jealous Lord"! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Why Evolve , when you Thriving!
No reason for the $ scam types to evolve. They seem to have lotsa suckers in Friam readership. I was amazed that correspondents even responded seriously. "Now, about that bridge..." Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Monday, May 23, 2011 10:00:08 AM Subject: Friam Digest, Vol 95, Issue 36 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. Re: Financial Scam (Nicholas Thompson) 2. Re: PC emulator written in JavaScript (Owen Densmore) 3. Re: PC emulator written in JavaScript (Alfredo Covaleda) 4. Re: PC emulator written in JavaScript (Jon Bringhurst) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Sherwood Physics, the Right Stuff!
Ruth and Bruce's books are truly excellent. I think Feynman would have approved. I wish I'd been taught their way. It would be nice to have them give a short series of well-chosen informal seminars on their ideas. For ignorant adults, if there are any in Friam. I am, and would learn a great deal. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] VORTICAL FLOWS and LIFT
The videos are wonderful, and I thank Nick, and agree with his opinion. As for the Theory of Tornadoes, it seems that to date it's literally a case of "God only knows"! But mebbe Friam, too. I have 1/2 century background teaching grad fluid mechanics at Caltech, Stanford, and USC and have done a lot of meteorological field work, but really wouldn't try to discuss the subject. I jus' dunno. One should remember that what one sees is a LOT less than what one gets, because that's where the tracer happens to be. This I expressed vividly to my students in auto design, when we took pix of airflow near bluff vehicles on test tracks in the Mohave Desert. A'course there is a huge billowing plume that presages before, and persists long after the vehicle is over the horizon. I remind them that it was not the "dust" doing this, but the air, and an identical disturbance occurs invisibly whenever a body passes through air. To paraphrase, "its bite is just as keen, although it is not seen"! Makes one take car streamlining seriously. I actually hold patents on one of those drag shield things that goes on the cab of a tractor-trailer rig, that was developed on NSF funding at our test base near El Mirage in the Mohave. Does good things for fuel consumption. It would seem likely that the sense of the vorticity in a tornado is related to the shear and Coriolis Effect ( Gaspard-G, 1835), although which way, I know not. I was manager of a big DOE program called the Coriolis Project for three years, so dealt a little with that. Lotta spin on the ball, there, literally! For smaller scale vortical flow Coriolis does not apply. Some interesting anecdotes: In East Africa, delightful Kikuyu tricksters, stand right on the equatorial line and for a few shillings will show you the exit vortex from plastic bucket, then move it north over the line a few feet into t'other hemisphere and "prove" that it rotates in the opposite direction. We seen this! Well, it really does, but not because of Gaspard-Gustave. In the Libyan deserts Holy Men will "attack" a dust devil, with much imprecation and flailing of a broad sword - and "kill" it. It just drops to the ground! You can see this. With your own eyes. Allah is indeed great! According to Bagnold, a great Brit desertologist and fluid mechanicer, whom I have used for some of his results, the secret is to determine in advance what the sense of the vortex is, and then to enter it on the upwind side, at just the right distance from the core, and flail around . It works, too. Ralph Bagnold, soldier, explorer and scientist, whose monumental work I'm lucky to have and reference, was portrayed in The English Patient. Pity when one is better known for a movie than an important book! The subject of how wings work is a much vexed topic. I was interested in what Nick said, but for my part, I don't think it is like that , and I reckon the air doesn't think so either. Authors, profs, and pilots (and I have been all three) are usually wrong on this topic. I respect only real airfoil designers on this issue , and have a few honest-ta-God airfoils named after me, that can be seen on the internet and in books. They all worked much better than we expected. In fact they have carried, safely, many men and women to record heights. There's an article in the Smithsonian about the first airfoil I designed, in 195 5, that me delightfool, but authoritarian, Teutonic boss-fuhrer , Herr Doktor Oberst Gustave Von ---, refused to name after me. Well, it flew nobly for the RAF, carried nuclear payloads in the good old, bad old days and kept the Ruzskies at bay. Mebbe!. I have given up noting the incorrect theories on lift. Life too short for that, although if one restricts one's discussion to things one knows conversation gets pretty limited. I am content to simply observe what the air does, and weakly agree with it, much as my intellect may reject that pusillanimous attitude. A s an expert witness, I have frequently quoted: "Theory crumbles before the Facts". Juries like it. But some years ago, while on the USC aero faculty, I decided to quit pointing out mistakes and publish my idea of the Truth. The paper (1996) is The Meaning of Lift , published as AIAA 34 th Aerospace Sciences Meeting, paper 96-1191. Funny thing is that, as a joke, I started calling it The Meaning of Life , and that has made it difficult to find by computer, but not by real people! Well, wot the Hell, for me and most of my fellow spirits up in the Big Blue, Lift IS Life! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscr
[FRIAM] Big Whorls have little Whorls!!
I missed the initial posting re Vortices! Can someone kindly repeat the question. I spent 50 years dealing professionally with vorticity and its curious consequences. Remember the Jabberwock, where his "Vorpal sword went snicker-snack!"? Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Friday, May 6, 2011 10:00:28 AM Subject: Friam Digest, Vol 95, Issue 7 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. How do these things WORK? (Nicholas Thompson) 2. notice the multiple vortices (Nicholas Thompson) 3. Re: off topic., but still (Mohammed El-Beltagy) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] ALL electro-magnetic machinery!
Isn't it true that all the above use rare earth magnets -- ALL electrical powerplants, cars, toothbrushes, cell phones? It is by no means exclusively a wind turbine problem! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] A modest proposal
The two nuclear plants in CA, San Onofre and Diablo Canyon, produce about 4.5 GW together. Both are coastline installations vulnerable to seismic and tsunami activity. CA total electrical power plant capacity is about 33 GW . In 2010 t otal "used capacity " for 100% full operation was about 26 GW. If the nukes were decommissioned , the loss is not too large and would have to be covered by wheeling power from adjacent networks . Neighbor states would like this and so should C alifornians. Why not! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Wednesday, March 16, 2011 10:00:06 AM Subject: Friam Digest, Vol 93, Issue 15 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. Re: Assistance sought: The meaning of constraints (Russ Abbott) 2. Re: Assistance sought: The meaning of constraints (lrudo...@meganet.net) 3. Re: Apocalypse in Japan (Alfredo Covaleda) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Work! Fer Gawd and Newton's sake!
Come on, Peoples! Work is DEFINED in Newtonian mechanics as being done "when a force moves its point of application". Thass all - and plenty enuff! So you lift a box up to a shelf - you doing work, as defined by Isaac, the Laborers Union and most Plain Folks. You put a whiskey jigger on a pool table - it and the table move , a very leetle bit, and work be done by gravity. Railroad lines represent useful constraints to freight cars. Thanks to them the car becomes an "object that moves in predestinate grooves"! The car is subject to acceleration due to all forces acting on it, but the rails try to keep it from cross track motion. They does their best - to the extent that they are capable. You may generalize the technical terms " force", "work" and "constraint " as far as you like. After all, they had meaning in language long before they were "defined" by Newton and La Grange for specific mechanical concepts. St. Paul (2 nd Corinthians III, 14) said: "The love of Christ constraineth us". I dunno what he meant, but the nice thing about the Bible is that you can choose for yourself what it means! It seems helpful to note that the tracks constrain the response of the cars to applied forces (more or less!). It's useful and human to employ the word in a more general sense, and it probably means roughly the same thing to most people. And if not, who cares? "What's in a name? " as someone said! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Forget not the Physics, Friam Friends!
It is fun to read Friamers’ hypotheses on formation flight in birds. They are entirely unprejudiced by any knowledge of the topic . Although knowledge of a subject is counter-friamistic and takes hard work, I modestly suggest that it is helpful to understand some of the aerodynamic principles behind formation flight before hyperventilating too much. The fact is that the Biot-Savart Law teaches that the asymptotic state is really quite close, as characteristic of a semi- infinite dipole field. Consequently, aerodynamics shows that for favorable interaction flyers can utilize uneven Vees, branched Vees, small Vees, big Vees, broken Vees – and migrating birds use them all. Or look as though they do! The tip station is theoretically the most unfavorable, but better than being solo. I have published seven papers on avian flight, and read and reviewed a good few more, so don’t know very much, but I would not presume any hypothesis on really why they do it, and who does what to whom. That’s for the birds! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Birdies do the right thing!
Yes, as always, Steve is correct. In my 1971 paper I included some stability calculations indicating that for a flyer moving ahead of the Vee line things became tougher, and vice versa. The funny thing, as noted in that paper, was that the lead bird, at the apex of the Vee, had the easiest job. This caused a lotta comment by ornithologists who had observed that the lead position was normally assumed by the oldest and senior bird. They asked, "Why would the strongest take the easiest job? ". My cynical answer was, "Twas ever thus, for Birds and Men!" Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] The Joys of Groupies
The Joys of Groupies I have read the interesting comments on the advantages of fish schooling. It all sounds reasonable, and is well worth hypothesizing. I like dealing with prosaic facts and observations, and quote a few established examples of avian and aviator group behavior that readers may enjoy. We know that formation flight, both the Vee and Echelon (one-sided Vee), confer significant aerodynamic benefits in reducing induced drag. I have fooled with this for some time now, from a 1971 paper in Science to a 2007 publication in AIAA. Whether the birds also know this is another question, although the advantages are so great (a theoretical 45% reduction in induced power) that one assumes they must have noticed. But there are other missions, and rationales for other formations. A particular hunting formation of the Brown Pelican (thriving again on the Pacific Coast since the abolition of DDT) is to fly a few meters above sea surface in roughly line-astern formation (actually with just enough echelon to avoid the wake of the flyer ahead). Lead bird will spot a surface prey, fold wings, dive almost vertically and snap up the imprudent fish. The standard operating procedure is to snag the prey with the front of the beak, that has a small hook, then to open beak, and smartly toss the fishie into the back of the gullet whence it can be swallowed. Doesn’t always work – there’s many a blip twixt beak and belly! If No. 1 misses fishie is left flopping around on the surface. Perhaps cursing his folly, but thinking he got away with it! Then No. 2 in the flight rolls over and takes a crack. It’s an easier target. Usually if all ahead have failed No. 6 will administer the coup-de-grace. I have observed this pattern for 4 0 years, and last week on a visit to the Coast, was delighted to see they still know how to do it. Bio-mimetics is a buzzword today. It is interesting to recognize that this pelican attack formation was copied by dive-bombers to great effect. In the Battle of Midway, and many others, USN squadrons flying the grand old Douglas Dauntless - the SBD (pilots claimed it meant “Slow, but Deadly”) - would attack target from astern (or out of the sun) in line astern, but from both port and starboard (to split the AA fire), often with the flight commander last in the line. It worked very well for us, due to courage and skill more than luck. The birds won’t say why they do things. One can’t talk to the animals, but can to people. In my youth, I was privileged to talk to the designer of the SBD, Ed Heinemann, and to work with many USN aviators who had been part of the Pacific War. Damned lucky we were to have then. We shall not look upon their like again! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Graphics Class, Excellent!
Yes, an excellent idea! I'd like to hear the times and days proposed. It sounds like a very worthwhile project. Let's hear more, ASAP! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Credibility, Schredability!
Wot i s this Thing called "Credibility"? How measured? And where listed? Ya want "credibility", go join the American Physical Society. Pay yer dues ($186 p.a., college degree not required) and you will be a member, in good standing, of a credible organization; they will publish your stuff, if it cleaves to the current dogmas. But, remember, over their vociferous objections, Dick Feynman resigned from APS on the grounds that he did not fit into their measure of a "credible physicist". I count myself a pretty ignorant bum, of parlous little knowledge in most everything. But I have never learned anything, cultural, literary or scientific from any Friam postings. I take them to be appealing examples of polysyllabic humor, oftentimes quite delightful. And not to be denigrated. S ince Aristophanes, comedy has been an honored component of world culture. And, fer Gawd's Sake, don't think of censoring contributions. I greatly enjoy Nick and Rich. They represent the epitome of the Friam Point of View! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Parsing the Bard
Shakespeare versus Friam! Oh, My! Seems like a hugely mismatched intellectual exercise! Well, Will wrote words for that, too! Perhaps: “A concatenation of cats”. Or: “What fools these mortals be!” It’s poetry, fellas! Didn’t anyone tell you? Before penning ab initio, ab ignorantio analyses, just study a leetle of the overwhelming volume of criticism on the Melancholy Prince. A good modern one, of the tens of 1,000’s of articles, is in Marjorie Garber’s, Shakespeare after All (2004). Read, and then write. But, but, but, to the horror of literalists, in the “To be, or not...” soliloquy (III, i) our forgetful Prince describes death as “The undiscovered country from whose bourn no traveler returns,” when two acts earlier (I, ii, iii), on the battlements, he’d actually been hearing some unpleasant revelations from his father’s ghost, “sy pappie se spook”, as the inelegant Afrikaans translation has it! Ah, consistency -- the hobgoblin of small minds -- but nevah the Bard’s! I view with delight all foreign versions of the play in “tongues unknown and accents yet unheard” that I can dig up. The Russian “Gamlet” (1964), with Smoktunovsky, and Shostakovich’s score, is pretty good. A darkly grand gothic revenge horse-opera. Much cold steel and poisoned chalices!! The Russian dialog is very impressive, sonorous and sinister, but a particular delight are the English captions. They are good, and grammatical, but weirdly, unaccountably, contain none of Shakespeare’s lines!! I have a vision of some good, grey Apparatchik Soviet State Translator, in the editing room earnestly listening to the spoken words and transcribing same into nice twentieth century English dialog with not the slightest inkling that there had actually been an English script (First Quarto, 1603), that a lotta Capitalists, over the centuries, found pretty inspiring! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Updike Vs the Bard
Define yourself. You'll be right! Me, I prefer Hamlet's definition: What a piece of work is a man! How noble in reason! How infinite in faculty! In form, in moving, how express and admirable! In action how like an angel! In apprehension how like a God! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Profiling!
It's all bluff and double bluff, etc. A wilderness of mirrors, as Jesus Angleton had it. A boy-actor, playing a girl, dressed as a boy, playing a girl, as the B ard wrote it. The reason to focus on annoying decrepid white grannies with enhanced inspection is to divert from the real target profile: young Middle Eastern males . Not such a bad idea! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] More Light, Less Touchy-Feely
I have followed the correspondence on enhanced scanning with usual mixture of shock and incredulity. Do people object because it’s offensive or because it’s ineffective? It would be unpleasant but, for me, unpleasanter to be blown up by a device that had avoided the enhanced scanner. But I haven’t enough info to make any definitive judgment. In particular on two matters. It seems that new bomb compounds can be concealed by flesh masses in exotic parts of the body without detection by the old scanners. I thought that the Xmas underwear bomber had proved this. It seems that old folk, handicapped people, children and infants are ideal subjects for planted bombs, with no adverse fall-out for the Bad Hats if detected. In this wicked world the innocent are always punished. If correct this is pretty awful news. The strategy is for a bomber to finesse that he’d be directed through the old system, pass and end up undetected on his planned flight. If an enhanced scan is required, then he should avoid this by all means while offering to take the old, ineffectual scan, and withdraw, undetected, unidentified and with his powder dry, to try again another day. In such circumstances he should behave like a gullible but superior person (e.g. a Friamer) and behave with all the histrionics necessary for the exasperated TSA to simply tell him to get lost. So this dramatic response, that some objectors seem to have chosen, and others to approve of, would make the objector highly suspect, and rightly so. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Art is a Lie
A’propos Ten Best Texts as fiction. I’m sure no one at Friam holds to the techno-barbarian view that nothing valuable can be gained from fiction. In my opinion the important human values can be illuminated only by fiction. After all, the King James Bible (1611) is about the best thing in fiction the English have ever done. When told that his work was “untrue”, Pablo* agreed, remarking: “ Art is a lie that helps us see the truth”. This seems a valuable insight. * Pablo Picasso (1887 – 1968): Sp., Fr. painter. Developed cubism Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] The snotgreen, scrotum-tightening sea!
a well known quote -- it's the on fourth page of Joyce's masterpiece, as I trow
all Friamers must know. I loved the "bestbeloved bestbook bash", and was
amazed that Ulysses headed the list. It is indeed great literature, or so they
say, but how does an ordinary yobbo read it? I was educated in the tongue
that Shakespeare spake, where he did, in fact, and always thought, with
youthful snobbery, I would gain something from this monumental tome. I had a
special interest in that my great uncle, a Dubliner, had known the real Buck
Mulligan personally, ("but not Mr. Joyce", as he respectfully qualified) and
so in grad school I took a course on the book. Formidable, but overwhelming!
I understand it a leetle now, thanks to the patient tutoring of Hallett Smith (
he wrote the definitive stuff on the S onnets), but really not very profoundly.
I truly can't believe anyone, even a Friamer, could pick up the volume cold and
derive anything from it.
Am I alone in my ignorance?
Peter Lissaman, Da Vinci Ventures
Expertise is not knowing everything, but knowing what to look for.
1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA
tel:(505)983-7728
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Bertie/Jeeves on Lost Positives
After some egregi ous faux pas with a titled lady, Bertie asks Jeeves, "Did you think the Duchess was disgruntled?" Jeeves replies, "That is not for me to say, Sir, but it was clear that she was very f ar from being gruntled." Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Bertie on Maths
Discussions of the "mea ning" of math are always interesting --- and revea ling. When I was a student of math at Cambridge B ertra nd R ussell was still around, and much in evidence. H e is supposed to have said, "M athematics is a subject where you don't know what you are talking about, and don't care if what you say is true". We smart-ass grad students thought that most entertaining. After all, the cano nical example is: "L et x equal y". Most ordinary folks found the remark very annoy ing, which , I suspect, was mainly its purpose. He is also alleged to have said, "P eople who discuss sex or mathematics usually don't practise it very well." Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Americans: Neither Ugly nor Dumb
Americans: Neither Ugly nor Dumb I have enjoyed the plethora of Wisdom apropos contemporary mores and innovation from Friam correspondents: finally a reply is irresistible. But I can respond only with banal facts I have personally experienced and know to be true. On dumth: I have earned a living in Africa, New Zealand , England and USA . During my years in the US I have found people to be generous, open-minded, honorable and mainly smarter than me. And folks here are significantly more civilized and humane than those in any other continent that I have worked in. So I am surprised at Friam correspondents’ apparent contempt for our fellow citizens - mebbe they know whereof they prattle, mebbe not. On innovation: the sage advice is all correct - and all irrelevant. I have spent decades working professionally with DARPA, NASA, DOD, US Renewable Energy Institute, many aerospace corps, and as a consultant for patent applications . I continually witness a brilliant, humbling, kaleidoscope of new ideas. I reckon, before pontif icating, pundits should establish qualifications of their own creativity: patents issued, original papers and articles, senior managerial accomplishments. Perhaps they are too modest to list these. I love reading the Friam stuff as fiction. I think Joyceans call it S tream of C onsciousness. It would be very nic e if people provided specific support for their assertions. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] MRI and brain research
On the Wi-Fi lunatic fringe ; I note that MRI is extensively used for brain scan research. Is there any possibility that this could affect people ? I remember in the ear ly days of X-ray it was dangerously over- used for medical diagnosis. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] A little Proof, Dr Thurston! It aint Elementary!
Who the Hell is Dr. Thurston? And how does he support his astonishing statement that mathematical proofs are "easier" than programming? I can respond only with my own experience. I was a mathematics scholar at the University of Cambridge (like Newton, but a little later). My supervisor and research director was a friend and colleague of Alan Turing. I always disappointed him in not fully understanding many of the established theorems of Analysis although, as with a computer today, I was able to use them very productively. I have vivid memories of studying in a medieval freezy student room in the wee post midnight hours, looking at two lines of Dedekind, and saying, "How in Hardy's name does that line follow that one?" Mathematics is a difficult subject, and, like playing the violin or compos ing sonnets, not everyone has the mind to do it. Programming is a beast of a different color. I have written and programmed a number of codes. Real ones; some used by NASA, others to design airfoils actually flown on record breaking aircraft, one, on wind turbine siting, sold here and in Europe at $25,000 a crack. They were tiresome to write, boring, detailed and demanding diligent programmers with more patience than I. But they involved no intellectual challenge beyond my limited apprehension . The above are just personal, factual statements. They PROVE nothing. But they do suggest from personal experience that Thurston's statement is BS. I mean, T heory crumbles before the F acts. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Physics and Philosophy
Yuss, and the really depressing thing about Physics is that people can prove you're wrong Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Monday, December 14, 2009 10:00:08 AM GMT -07:00 US/Canada Mountain Subject: Friam Digest, Vol 78, Issue 13 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. Physics and philosophy (Robert Holmes) 2. Re: Physics and philosophy (Douglas Roberts) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Physics and Philosophy
Yuss, and the really depressing thing about Physics is that people can prove you're wrong Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Monday, December 14, 2009 10:00:08 AM GMT -07:00 US/Canada Mountain Subject: Friam Digest, Vol 78, Issue 13 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. Physics and philosophy (Robert Holmes) 2. Re: Physics and philosophy (Douglas Roberts) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Pressure and Noise!
Nick is absolutely correct! An increase in pressure causes an increase in density of most fluids, as noted by Sir Robert Boyle in 1662. The thing is: air be so light that changes in speed involve only tiny pressure and density increases, of a few per cent, less than occurs during a storm front passage. So can safely be ignored and the whole wonderful century- old mathematical discipline of incompressible fluid mechanics becomes almost correct ! And true enuff!! The genius of aerodynamicers has been to convert this teeny-weeny pressure difference into a force enough to lift tons of weaponry, or i nnocent vacationers, across half the globe in fractions of a day ! It has always been an exhilarating thought to me, and gra tifying to have had some tiny part in its provenance. A'course the birdies knew it all along, and in the case of the ravens of Sant F e, almost seem to "understand" lift!! I gav e a seminar on that at Caltech recently, and offered it to Friam, but no-one around here seems interested! I was shocked on the internet to see many " scientific" elementary discussions of the grand ol' Boyle's Law make no reference as to its date, the character of S ir Robert and how he got to that great realization . How can ya expect kids to have any sense of history when elementary science writers are such boors? And, Yes, Nicholas there are huge changes in pressure and density with altitude in the atmosphere, that fundamentally give us that popular, ubiquitous and inescapable phenomenon, the weather! It's easy to see the air near the surface of our earth is carrying, on its back, all the air above it, and so is pretty heavily laden. More, I think, tha n that turtle down at the South Pole that carries E arth on its back. Now flow speeds in the earth atmosphere (not on other planets) are low enough that compressibility due to speed doesn't change density enough to be of any importance. So terrestial meteorology fluid dynamics is incompressible but of importantly varying density. The subject of terms and usage is certainly of interest. W hen I taught this stuff, at Caltech, Stanford, USC, USN, I tried to interest students in the meaning of words, on the grounds that it was not only kultured , but also a way of understanding phenomena more profoundly. I don't think my sermons were very effective. Pity. For example, if one defines "stability" as a property where "a system with multiple states returns to the initial after a disturbance", then one finds it works for elastic, dynamic, mental, political, financial, eco logical stab. And has a vivid meaning. I think the popular usage was coined mainly by Routh in 1905 in connection with dynamic stability. Yeah, the date's correct. Them old SOBs wuz doing vehicle stability same time as the Wrights were first fluttering around! Ya gotta admire theoreticians of N atural Science. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Speculation, and other folly!
John Dabiri is not a Caltech aerodynamicist, and has never published on wind energy, propellers or rotors. My thesis was on wing theory at that institute, I taught there for many years, and have published many papers, monographs and bits of books on the subject of wind turbines, including a lot of stuff on design of rotors and arrays. I don't k now what he knows, but I do know sumpin! But validity depends not on pedigrees but results! The article in Physics is pretty bad, for example, contrary to the author's statement, prop turbines do not shed vortices, but annular vortex sheets, with a lotta turbulence, a very different animal, that I have often analyzed, tested and measured in wind tunnel and field. I was concerned at his naive statement that the power increases because the rotational speed increases. It's elementary dynamics that this is not necessarily so. The power is the product of speed and torque, and for many turbines the power reduc es as the rotational speed is increas ed! In fact, in design studies, we often would feather, causing a unit to speed up and reduc e power output. For example, a prop anemometer spins very fast, extracting no energy from the wind, at essentially zero torque (except bearing friction). If it is braked by a motor, then the spin reduces as the power produc tion goes up. I dunno what John's paper is about, haven't read it. It is always good when an outsider introduces a new idea into a field. S o I'm looking forwards to hearing. I am amazed at folks tenacity to an idea that they don't even understand! But like the sound of, I presume! I have no opinion on the subject, because I haven't seen the pap er. When I recei ve same, I'll discuss for Fria mers. I don't want to waste folks' time on conjecture. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Array Interference
Nick notes that there's something funny if an array reduces effective wind for a peleton of sweaty b icy clistes, but increases it for a bunch of spinning turbines. And he's dead right! A nd these are legitimate, rational questions that an intelligen t layman should ask. The answer is that the science writer is propagating BS, as is often the case. Did anyone hear it? I have been in contact with the autho r , my friend, John Dabiri, who told me they weren't ready to release their paper yet but he'd send me ASAP! When I study it, I'll brief Friamers on the content, and its validity. I dunno! And I'd like to read. Dick Feynman used to say unofficially that he never read papers, but if you told him the title and the author , he would tell you what it was about and why it was wrong!! A good approach for genius , but bey ond me! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Hot Air, and Compressibilty
Hot Air, and Compressibility A’course air is compressible, and so is water. Any kid who fools around with bicycle pump or a shock absorber, and believes what he sees, rather than what he is told, can feel the compressibility. But, but, but, at modest speeds free air will NOT compress and prefers to “run away” rather than doing so. For example, if you sweep your hand through the air, the flow runs away and, although the pressure on your palm is higher than static, there is virtually no compression of the fluid. You have to sweep your hand at a speed comparable to that of sound (about 330 m/s here on earth) in order stop the air from getting away and to achieve any compression. Since, according to my latest studies on musculature, the maximum speed of an Olympic discus hurler is about 33 m/s, we’re not likely to experience that. Anyhow, the effective incompressibility of air is taught Day 1 in Aerodynamics 101! The reason WHY is reserved for four years later in grad school! Surely anyone who can read today has heard of the “sound barrier” or seen the movie, if you can’t read. Many folks in the West have experienced a sonic boom. All this has been known since 1890 and was described, analyzed and measured by Herr Doktor Ernst Mach, a product of that golden milieu of scientific thinkers, the old Austro-Hungarian Empire. Mach was a rare bird, being an intelligent philosopher who discussed physics with Einstein. H e didn’t agree with Special Relativity. Wrong there, Ernie! Some people have heard of his number – certainly all test pilots. I instructed many in the Navy. I painfully learned this stuff, and used the instrument Mach invented, the Schlieren, in my early days as a grad student, battling with shock waves in a grimy subterranean Wizard’s Cave, the Hypersonics Lab, not at, but underneath Caltech! All the above info I stand behind, and have published on. It’s not conjecture or anecdote. I don’t discuss things I don’t understand. Like most scientists, I am an ignorant fellow, oblivious to the vast majority of human knowledge, but enjoy being enlightened by folks who do know. It is not dumb not to know things, but it is to think that your own knowledge encompasses physical truth on subjects on which you are ignorant. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Wind Farm Comprssible Flow!
I didn't know that wind tur bines experienced compressible flow. This makes all my papers and books on the subject wrong, although the operating turbines designed by my codes don't seem to know this! I would like to correct them. Can anyone provide reports on compressible flow in wind farms? Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Thursday, November 26, 2009 10:00:07 AM GMT -07:00 US/Canada Mountain Subject: Friam Digest, Vol 77, Issue 30 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. Some Facts about Arrays! (plissa...@comcast.net) 2. Answer to Steve! (plissa...@comcast.net) 3. Re: flocking windmills (Roger Critchlow) 4. Shrink Wrapped Bikes (plissa...@comcast.net) 5. Re: Shrink Wrapped Bikes (Hugh Trenchard) 6. Re: flocking windmills (Marcus Daniels) 7. Re: Some Facts about Arrays! (Marcus Daniels) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Shrink Wrapped Bikes
In the 80s we did a lotta work on that, designed, built and tested them. Didn't talk, did! The shrinkwrap is actually a shape like a vertical streamlined fin, narrow and tall, on a light stringer airframe covered with Monokote, that encloses the frame and rider. Huge benefits obtain from this. In the course of our road test work at the old Ontario Race Track we achieved human powered speeds in excess of 55 mph, and, as a delightful touch, prevailed upon a CA Highway Patrol officer to come pace us officially , and give the rider a ticket for exceeding the freeway speed limit; in those energy confused days it was 55 mph! Streamlined bikes are not much use. You need a few warm bodies to drop the fairing on you and set you up. And, of course, crosswinds are the very bugger! We had some very effective ideas for the Olympics (I worked for that committee) but, predictably they were so good that they were all banned! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Answer to Steve!
Array models are muc h more sophisticated than he could even understand. The simplest models use Fourier tranforms for the boundary layer effects on the lumpy terrai n, and, for the wake development, turbulence levels computed from interaction of atmospheric stability, ground roughness, tur bine sca le, energy ex traction and wind speed gradien ts . A nd it's still not complete, but tests on my ancient model in Swed en on a real 200 kW unit spinning in the Baltic breeze were not too bad Why not put in all the effort? There's lotsa $ involved. A nd dont' even think of relo c ating a 1/2 mill $, 500 kW unit, the transfer would eat up 10 years profits! It's a mistake to assume folks know less than you! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 - Original Message - From: friam-requ...@redfish.com To: friam@redfish.com Sent: Wednesday, November 25, 2009 7:33:24 PM GMT -07:00 US/Canada Mountain Subject: Friam Digest, Vol 77, Issue 29 Send Friam mailing list submissions to friam@redfish.com To subscribe or unsubscribe via the World Wide Web, visit http://redfish.com/mailman/listinfo/friam_redfish.com or, via email, send a message with subject or body 'help' to friam-requ...@redfish.com You can reach the person managing the list at friam-ow...@redfish.com When replying, please edit your Subject line so it is more specific than "Re: Contents of Friam digest..." Today's Topics: 1. Re: flocking windmills (Steve Smith) 2. Re: Dunbar numbers and distributions (Steve Smith) 3. Re: flocking windmills (Roger Critchlow) 4. Re: flocking windmills (Marcus G. Daniels) 5. Re: "model" ( was Re: Dunbar numbers and distributions) (Steve Smith) 6. Re: Dunbar numbers and distributions (Steve Smith) 7. Re: Dunbar numbers and distributions (Nicholas Thompson) 8. Re: Dunbar numbers and distributions (Nicholas Thompson) 9. Re: "model" ( was Re: Dunbar numbers and distributions) (glen e. p. ropella) 10. Re: Dunbar numbers and distributions (glen e. p. ropella) 11. F'ing Windmills (plissa...@comcast.net) 12. F'ing Windmills! (plissa...@comcast.net) 13. Re: Dunbar numbers and distributions (Nicholas Thompson) 14. Re: Dunbar numbers and distributions (Marcus G. Daniels) 15. Massively collaborative mathematics (Mikhail Gorelkin) 16. Re: flocking windmills - bike race model (Hugh Trenchard) ___ Friam mailing list Friam@redfish.com http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Some Facts about Arrays!
I assume FRIAM folks want to increase their knowledge - or mebbe not. Credentials: I have supervised wind tunnel tests of vehicles in arrays at USC and made extensive theoretical calcs with grad students on this subject , have tested my own designs (the Sunraycer and GM Impact) in the Caltech tunnel and the GM tunnel, and probed the wakes. I have driven instrumented test vehicles in the wake of bluff bodies at a decommissioned airfield in CA, at our test base at El Mirage Dry Lake, CA, and the GM Proving grounds in AZ. It's pretty hairy. I hold the patents on two truck drag reduction airshields. Here's the received knowledge, that I take to be correct: There is NO SUCH THING AS A BOW WAVE in incompressible continuum flows. The field equations are elli ptic, won't permit same, and Nature agrees! Bodies in a fluid stream create a wake of low energy flow that trails behind ( but NOT as a CYLINDER!). Statements that wak e pathlines are longer than in undisturbed flow are correct. The idea that this somehow forces the flow to go faster is VOODOO fluid mechanics that I didn't know was still accepted. Wake flows are actually much slower than freestream. Said wake contains a lower energy flow, and lotsa turbulence. It extends for about 12 scale lengths astern of the body, until re-energzied by turbulent entrainment from the surrounding flow. The drag of a body immersed in this wake is significantly reduced (but not the drag coefficient). For bluff bodies like cars, bikes or peoples the velocity deficit of the wake is very pronounced. The wake is influenced by ground effect (unlike the prop turbine case), and is very turbulent, with eddies of about the same as the body scale, especially when the body does no work on the flow, as is the case with bikes etc. There are no "lifting" components here (at least in the correct, nonFRIAM, use of the word), but severe crosswind disturbances usually occur. These wake effects are us ed to great advantage in peletons and in drafting for formula race cars. And also by crazy people (like one of my professional drivers, since killed !) for fun behind trailers on freeways. There's no mystery about anything in this sort of array interference, except the apparently eternal riddle of turbulence. I'll be glad to answer furth er questions, if I know the answer! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] F'ing Windmills!
F’ing Windmills It is good to see FRIAMers enthusiastically holding forth on another area of their whimsy – the effectiveness of wind turbine arrays. Wind Energy can provide a significant contribution to our energy supply. Understanding it helps. Commenters might be interested in the first seminal paper, Energy Effectiveness of Arrays of Wind Energy Collection Systems, (1976), by a clown, name of Lissaman. This paper has been referenced and improved upon many times in the last 30 years. The most recent revision, by the same author, appears in the book, Wind Turbine Technology, published by NASA, and reprinted by ASME in 2009. It’s ancient, but the principles, and our planetary boundary layer have not changed. The article in Science Magazine is an example of bad science reporting, illustrating the red neck passion to simplify subtle issues into easily understandable syllogisms (see contemporary Republican politics). The reporter discusses “new” vertical axis machines! The Darrieus Vertical Axis Wind Turbine was new in 1971, while the Savonius VAWT goes back to 1931. So much for the writer’s research! That history is in most encyclopedias. In 1976, I gave a paper at the International Wind Energy Congress in Cambridge , England , funded by US DOE, noting that the then new VAWTs were not cost effective compared with the propeller type. I think that’s still true. The FRIAM response seems a little like superficial science; thinking things that “look like” or “sound like” something are that thing. An intelligent, but untutored, opinion may be interesting in philosophy, it usually isn’t in science. FRIAM is supposed to be a place where knowledgeable folks can share it. For those interested: On complex terrain there are locations that have strong flows. This is a function of topography and wind direction. One would like to install Wind Energy Collection Systems at these locations. Usually space is limited, so some WECS units will be in wind shadows, sometimes. The array can be designed to maximize the annual energy capture. This requires annual detailed wind records, a model to compute the flow over complex terrain and a turbine model describing the turbulent wake and its dissipation -- indeed a complicated process well suited to modern computers, and dependent still on poorly known fluid physics, especially atmospheric turbulence. The economic trade enters next, where costs are reconciled with the reduced revenue of units in dense arrays. From hence cometh the most effective array – not always the max. capture case. And, because costs are time variant, different each year! The ideas are simple, the execution exceeding tiresome! In the dark ages of wind energy, with funding from SBIR and DOE, Lissaman and Quinlan developed, and AeroVironment marketed, a software model, AVENU, by which one could take a contour map of a site, define a wind speed and direction, place multiple turbines on it and compute the total energy capture, including interference. One could then drag the turbines to putatively better locations, and observe the effect. Easy on a computer, not so in the cruel world! I always thought that the verb “drag” was especially vivid here, having actually, with a cursing crew, moved 30-ton turbines by dragging them from one piece of California low desert to another. We sold the software here and abroad for $25,000 a crack, including a free Mac II, since our European customers were PC operators. It was not a successful product financially, but has been used extensively in array design for the last 30 years. I have not read my friend John Dabiri’s Caltech report, but have put in a call to chat to him. I taught wind turbine stuff at Caltech to grad classes when John was in grade school, and expect that his will be an excellent contribution. I will report on same to FRIAM when I have studied the paper itself. My title, “f’ing”, referred to “flocking”, certainly a very interesting phenomenon, as is the other possible adjective. One can achieve favorable array interference in water, air or on land. I have made technical contributions to all: wet, dry and dirty flocking. The conclusions are sometimes surprising. For example, in a Vee formation of migrating geese the leader, at the tip of the Vee, experiences the most favorable interference. It’s nothing like “breaking the trail”, the magical anthropomorphical explanation! Since I published this in 1970, folks have asked why the strongest Alpha animal would take the easiest position. My reply is, “They ain’t Boy Scouts! If you were the strongest member of the team, wouldn’t you take the easiest job?” I would, and do, as does every FRIAMer who employs a gardener! Peter Lissaman, Da Vinci Ventures Expertise is not
[FRIAM] F'ing Windmills
F’ing Windmills It is good to see FRIAMers enthusiastically holding forth on another area of their whimsy – the effectiveness of wind turbine arrays. Wind Energy can provide a significant contribution to our energy supply. Understanding it helps. Commenters might be interested in the first seminal paper, Energy Effectiveness of Arrays of Wind Energy Collection Systems, (1976), by a clown name of Lissaman. This paper has been referenced and improved upon many times in the last 30 years. The most recent revision, by the same author, appears in the book, Wind Turbine Technology, published by NASA, and reprinted by ASME in 2009. It’s ancient, but the principles, and our planetary boundary layer have not changed. The article in Science Magazine is an example of bad science reporting, illustrating the red neck passion to simplify subtle issues into easily understandable syllogisms (see contemporary Republican politics). The reporter discusses “new” vertical axis machines! The Darrieus Vertical Axis Wind Turbine was new in 1971, while the Savonius VAWT goes back to 1931. So much for the writer’s research! That history is in most encyclopedias. In 1976, I gave a paper at the International Wind Energy Congress in Cambridge , England , funded by US DOE, noting that VAWT were not cost effective compared with the propeller type. I think that’s still true. The FRIAM response seems a little like superficial science; thinking things that “look like” or “sound like” something are that thing. An intelligent, but untutored, opinion may be interesting in philosophy, it usually isn’t in science. FRIAM is supposed to be a place where knowledgeable folks can share it. For those interested: On complex terrain there are locations that have strong flows. This is a function of topography and wind direction. One would like to install Wind Energy Collection Systems at these locations. Usually space is limited, so some WECS units will be in wind shadows, sometimes. The array can be designed to maximize the annual energy capture. This requires annual detailed wind records, a model to compute the flow over complex terrain and a turbine model describing the turbulent wake and its dissipation -- indeed a complicated process well suited to modern computers, and dependent still on poorly known fluid physics, especially atmospheric turbulence. The economic trade enters next, where costs are reconciled with the reduced revenue of units in dense arrays. From hence cometh the most effective array – not always the max. capture case. And, because costs are time variant, different each year! The ideas are simple, the execution exceeding tiresome! In the dark ages of wind energy, with funding from SBIR and DOE, Lissaman and Quinlan developed, and AeroVironment marketed, a software model, AVENU, by which one could take a contour map of a site, define a wind speed and direction, place many turbines on it and compute the total energy capture including interference. One could then drag the turbines to putatively better locations, and observe the effect. Easy on a computer, not so in the cruel world! I always thought that the verb “drag” was especially vivid here, having actually, with a cursing crew, moved 30-ton turbines by dragging them from one piece of CA desert to another. We sold the software here and abroad for $25,000 a crack, including a free Mac II, since our European customers were PC operators. It was not a successful product financially, but has been used extensively in array design for the last 30 years. I have not read my friend John Dabiri’s Caltech report, but have put in a call to chat to him. I taught wind turbine stuff at Caltech to grad classes when John was in grade school, and expect that his will be an excellent contribution. I will report on same to FRIAM when I have studied the paper itself. My title, “f’ing”, referred to “flocking”, certainly very interesting phenomenon, as is the other possible adjective. One can achieve favorable array interference in water, air or on land. I have made technical contributions to all: wet, dry and dirty flocking. The conclusions are sometimes surprising. For example, in a Vee formation of migrating geese the leader, at the tip of the Vee, experiences the most favorable interference. It’s nothing like “breaking the trail”, the magical, anthropomorphical explanation! Since I published this in 1970, folks have asked why the strongest Alpha animal would take the easiest position. My reply is, “They ain’t Boy Scouts! If you were the strongest member of the team, wouldn’t you take the easiest job?” I would, and do, as does every FRIAMer who employs a gardener! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing wha
[FRIAM] Facebook & Sex
Isn't it rather like sex? If you need people to tell you what t o do with it , it's not for you! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 ://redfish.com/mailman/listinfo/friam_redfish.com FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Wot's Nu, reprise!
I find it a puzzlement, and a wee bit like hubris, that folks communicate on the internet, instead of under a fig tree, confirming their personal views that there is "nothing new"! I speak from ignorance, but is satellite commo, solid state electronics, quantum mechanics and electro-optics old hat in the universe of philosophers? Me thinks my Lord Hamlet said it again when he remarked to Horatio, "There are more things in heaven and earth than are dreamt of thy philosophy ". Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Wot's New, Doc? Plenty, Bugsy
The above question can be answered at some level for the Bugs Bunnys of the world! And the answer is: Yes, indeed, plenty. Here is a little story anent our marvellous aptitude for development with time. The original discus, as used in the first Greek Olympics, was quite clever, and actually went further than anyone could throw a sphere. It s range was about 65 m, still close to the modern Olympic record. In 1961, as a low speed aerodynam icist at Caltech, I worked with some characters from Whammo on a funny looking plastic dish, that we called Frisbee and guessed we might sell a few 1000. We were off by a few million on that market prediction! The latest disc variant, called Aerobie, holds the record range of more than 300 m, as listed in Guinness. It is appealing to note that this is comfortably the furth est any object ha s evah been thrown by the hand of Man! We are now working on improving this. There are a few factors: air density: unchangeable, gyroscopic precession: invariant, at least according to Newton, human musculature:slowly improving: and disc design: improving by leaps and bounds. I am familiar with this since I have been involved in this stuff for 40 years, and have been invited to give a paper next S ummer at an International Symposium in Vienna on my latest efforts on disc design and flight dynamics prediction. So I see lotsa new things , Bugs. And they do not reside in verbiage , but, in this case, in an axisymmetric plastic disc that you can pick up in your hands, hurl and see with your own eyes wheth er it is any better! Not "Words, words, words," as my Lord Hamlet complained ! But reality - if that means anything! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Wiki math
Folks are complaining about Wiki math. For what it's worth, and only on subjects that I have some applied knowledge, Wiki's views on math are very shallow and sometimes actually wrong, and provably so. For the former, I refer to Bessel Functions (that Jeffries and Jeffries called "a long sad tale"!) where their take is OK if you just want a number, but horrible if you want understanding, and behavior near singularities. Sort of like saying a numerical table of trig functions is the meaning of trigonometry! For an error, their equations on gyroscopic precession are simply wrong. I know most people don't have an intuitive feeling for this, and there are many idiotic physical "explanations". And understanding it correctly doesn't matter so much, unless you are a spinning projectile. I use this stuff for real for actual spinning spacecraft. Hate to try to develope the equations of motion using Wiki's section! I get the feeling that much of the mathy Wiki is written by "true believers" who are actually not professional, but have painfully learned algebra by rote, never been challenged by good profs, and delight in their "understanding". I suspicion the folks who know the "real" truth can't be bothered to correct the amateurs. This is a nice type of input for historical and literary matters, but not so good for rational science. So don't take Wik i too seriously on math matters, unless you know how to unearth the truth. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] NYT Blather on Turbulence!
If you believe that article you will believe anything! I was shocked that the author refers to Lagrangian reference systems without understanding or ever describing what he means (it's the most simple concept), blathers on about large scale high Reynolds Number Turbulence in Monterey Bay surface flow and ends with George Haller, who when I discussed this with him personally last year was doing experiments in low Reynolds Number flow in about the "creeping" range. That's viscous oil schmearing around beercan sized 2-D circular prisms at about 1 cm/sec.! Not exactly the otter-haunted kelp-infested shoreline of the Bay. Also, none of this has anything to do with drag of bluff bodies (automobiles) as George admitted to me, also that his stuff does not apply to turbulent flow, and that the last article on his work was also very deceptive. Nothing wrong with the work of anyone he mentions, just with the "science" writer himself! Gimme a break. Reporters don't have to know the arcana of turbulence, but should submit their stuff for review to someone who does! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Help, Please!
Wanted: a hands-on computer consultant for MATLAB, for pay! My place in SF or yours. ASAP for invited scientific paper. Please reply by e-mail. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 --- Begin Message --- Doug has found the fundamental answer to all of our questions by synchronous morphic resonance? Whow. Maybe his parrot farm is just a nickname for a huge subterranean data center which dwarfs Google's latest and biggest versions? I am impressed. -J. - Original Message - From: Steve Smith To: The Friday Morning Applied Complexity Coffee Group Sent: Tuesday, September 22, 2009 10:58 PM Subject: Re: [FRIAM] ABMs and Psychology I think you've hit upon the fundamental answer to all of our questions, philosphical (synchronicity vs emergence and epistimology vs cosmology), technological (what is the bestest language for OO or ABM development), psychological (variations on homunculus talk), mathematical (is solving Goldbach's conjecture fundamentally more important than Fermat's last theorem?), and practical (is it too late for coffee yet too early for beer? And in what Time Zone?) All of these FRIAM discussions do seem to be about infinite horizons and somebody always demands that we return to experiences. Amazing... Synchronicity *and* Morphic Resonance all rolled into one! ;-} Steve --- End Message --- FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] Manifold meanings!
Why not stick to the poetic usage - "with ardours manifold"? Otherwise what difference does it make unless you wish to use it in an unambiguous sense for some operation, in which case you can define it in a useful fashion. Incidentally, in all my post grad studies of mathematics at Caltech and Cambridge I never heard of a function's having to be single valued. For example, asinx has an infinite number of values for any real argument, x, and a set more if x be complex. Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
[FRIAM] More in heaven and earth!
I know not what or how philosophy lead to DNA, or the transistor, or Shannon's Theorem, or Darwin's thoughts. I would be interested in being informed about how classical philosophy is on the frontier of new concepts in Natural Philosophy. I reckon My Lord Hamlet had it right when he said, "There is more in heaven and earth, Horatio, than is dreamed of in your philosophy." Any way you interpret the line! He also complained to Polonius, "Words, words, words"! Sounds like a philosopher! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728 FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
