The Value Of An Apology, At Least From A Republican's Perspective!!
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From: Neil Harrington on 27 Sep 2009 14:49 "Chris Malcolm" <cam(a)holyrood.ed.ac.uk> wrote in message news:7i8u6lF30hncfU1(a)mid.individual.net... > In rec.photo.digital Neil Harrington <secret(a)illumnati.net> wrote: >> Chris Malcolm wrote: >>> In rec.photo.digital D. Peter Maus <DPeterMaus(a)worldnet.att.net> >>> wrote: > >>>> No one has ever said that the bumblebee can't fly. Clearly it >>>> can, it happens every day. Science has never been so blind as to >>>> make such a claim. But what Science HAS said, is that the bumblebee >>>> is UNSTABLE in flight, an aerodynamically unsound design. This >>>> doesn't mean or even imply that it can't fly. Just that there would >>>> be easier and better ways to achieve flight. >>> >>> Not so. What science said until recently was simply that according to >>> our understanding of fixed wing aeroplane flight the bumblebee had >>> insufficient wing area to fly. > >> That's the story as I always heard it too, "insufficient wing area to >> fly." > >> But the idea that "SCIENCE said" that is something I'm very skeptical >> about. >> What sort of science could possibly arrive at such a conclusion? > >> In the first and most obvious place, a bumblebee is in no way comparable >> to >> a fixed wing aircraft. What it is comparable to is an ornithopter, and I >> don't think anyone ever built an ornithopter that could actually fly, so >> that's a kind of aircraft that you wouldn't expect there to be enough >> scientific data on to arrive at any conclusions about bumblebees. > >>> Not that it was unstable. It is in fact >>> unusually stable in flight due to its relatively low centre of gravity >>> and large effective dihedral. > >> How do you establish the "effective dihedral" of wings that are beating >> at >> such an incredibly fast rate, though? > > The point about dihedral is that as the plane (or insect) tips over to > one side the effective length of the wing on the lowered side > increases, increasing the lift on that side, and the effective length > of the other wing decreases, decreasing the lift. So the forces > naturally restore level flight. At a first approximation you could > simply average over the range of motion of the flapping wing. As a > second approximation you could assume simple harmonic motion of the > wing and average over that, which would lead to much the same result > :-) > > Or experimentally you could use high speed photography to map the > trajectory of the flapping wing and integrate, or simply measure the > forces (recent analysers of bee flight have developed various ways of > doing all that). > >> I don't believe dihedral has anything >> to do with it. > > I didn't say it had anything to do with the claim of bees not being > able to fly. You raised the red herring of that claim having something > to do with stability. No, that wasn't me, that was Peter. I don't believe bumblebees either have or require stability in the sense that fixed wing aircraft do. > I used the dihedral and low centre of gravity of > the bee to point out that stability wasn't a problem in bee flight, > and wasn't what the controversy was about. Bees are amongst the most > basically stable of insect fliers, simply because their "design" is > optimised for the carrying of heavy loads -- they're big nectar > tankers for transporting nectar loads back to the hive. Regardless of > exactly what the exact effective dihedral of a bee's wings is, there's > no doubt that there's quite a fair dihedral. Modern high speed > photography has shown that. > >> Even if you could calculate the AVERAGE dihedral of a >> bumblebee's wings, you'd still have to establish the incidence in order >> for >> it to mean anything. Dihedral produces lateral stability only because (or >> if) the wing also has positive incidence. > > I think you're confusing incidence with angle of attack. Yes, the goof occurred to me after I'd written it. It's incidence with relation to the aircraft, but angle of attack with relation to the air mass which is of course the important thing. > Given a bee's > bent and rather unaerodynamic shape, and the fact that it flies with > its undercarriage down, it would be hard to decide what the > longitudinal aerodynamic axis of a bee's body in flight actually > was. The bee wing angle of attack varies all the time as the wing > moves. But what the angles are doesn't matter. All that matters for > dihedral to work is that lift is being generated by wings. It doesn't > matter how. Since bees do actually fly then lift is obviously being > generated therefore dihedral effects occur. I still don't believe that dihedral has anything to do with it. As long as the bumblebee can produce thrust, which obviously it does, and instantaneously direct that thrust as required to either move or stay in position, it shouldn't need dihedral or anything else for stability. Consider the Harrier, for example. When it's hovering its wings (which don't have dihedral anyway, they have pronounced anhedral) aren't doing anything; the aircraft is just sitting on its thrust. I think that is basically what the bumblebee is doing. > >>> The problem was that theoretically the >>> wings weren't large enough to do the job they clearly were doing. So >>> something was wrong with a simplified analysis of bee flight based on >>> fixed wing aerodynamics. >>> >>> In the 1990s the important missing factor was discovered -- the >>> trailing edge vortices which are such an important source of lift loss >>> in fixed wing aerodynamics were exploited to add lift in the flight of >>> many insects. In the 2000s high speed cinematography and mechanical >>> simulations of bee wing motion demonstrated in practical detail that >>> this was in fact what the bee was doing. > >> That's interesting. > >> I'd still like to know where the original "insufficient wing area" story >> got >> started, though. Absent some proof of a serious scientific analysis in >> the >> past claiming that, I'm inclined to believe it may be more of an urban >> myth. > > It has been difficult to track down the source of the claim. According > to Wikipedia the earliest published claim comes from the introduction > to "Le Vol des Insectes" in 1934 by the entomologist Antoine Magnan, > who was relying on unspecified calculations done by his assistant > Andre Sainte-Lague. > > But the story was verbally current long before that publication. > > What Wikipedia says about that is that > > "Some credit physicist Ludwig Prandtl (1875-1953) of the University of > Gottingen in Germany with popularizing the myth. Others say it was > Swiss gas dynamicist Jacob Ackeret (1898-1981) who did the > calculations." > > and more generally > > "It is believed that the calculations which purported to show that > bumblebees cannot fly are based upon a simplified linear treatment of > oscillating aerofoils. The method assumes small amplitude oscillations > without flow separation." > >> It's a popular one anyway, and will probably go on forever -- like the >> widely held belief that before Columbus everyone thought the earth was >> flat. > > Such beliefs would soon die out if we gave our children a better > scientific education. The problem is that a lot of people, especially > in the US, think that our children are already being exposed to too > much science, I've never heard anyone make that complaint. The problem in the U.S., I think, is that much of our primary education is a waste of time and money. We have some very good schools but apparently a lot more really lousy ones. I have read that young people going from high school into the armed forces (which you would expect high school to be enough to prepare them for) often have to be given remedial education on entering the service, before they can be trained to actually do anything. And I know for a fact that our local community college -- and presumably all community colleges in the state -- routinely gives new students, who of course have graduated from high school, a fairly simple reading comprehension test to see whether they require remedial education in English before they can do anything else. > which carries the danger of encouraging scepticism about > the literal truth of religious scriptures believed to be the Word of > God. I doubt that's a major part of the problem. The worst of it seems to be in the inner cities, where some young people graduating from high school are handed diplomas which it is said (perhaps with slight exaggeration) they cannot read. In those places I don't think concern over religious scriptures or the Word of God is really much of a factor in poor education. What is a factor is the problem of teachers' unions, which make it impossible to get rid of worthless teachers. Also, again in the inner cities, is the really big problem of lack of discipline. Where the teachers are afraid of the students -- often with good reason -- the schools are unlikely to produce well-educated graduates. > The "according to science bees can't fly" is a very popular > simple way of explaining to ignorant gullible people why they > shouldn't trust science. And so long as plenty of people are making > plenty of money out of encouraging people to distrust science it's > bound to go on. Yes, but that is true even among some well (or at least expensively) educated people.
From: Neil Harrington on 28 Sep 2009 14:13 "tony cooper" <tony_cooper213(a)earthlink.net> wrote in message news:m8kvb5d7pru1c4rdoqh0gu6ikvc77noam8(a)4ax.com... > On Sun, 27 Sep 2009 15:26:58 -0400, "Neil Harrington" > <secret(a)illumnati.net> wrote: [ . . . ] >>>> >>>> Some nice weapons. >>>> http://tonycooper.smugmug.com/photos/651843003_LrGXM-L.jpg I had to >>>> photograph them as they sat. Not a good thing to go re-arranging >>>> someone else's guns for a photograph. >>> >>> A brace of Ruger Vaqueros and a Marlin rifle, I believe. >> >>The sixguns are Rugers all right, but the rifle has me stumped. The bolt >>sure looks like a modern Marlin lever action, but it appears to be a slide >>action rifle. I don't believe Marlin has made a slide action rifle in many >>decades, and when they did they didn't look like that. >> > > I don't know if this is the same rifle, but I think it is. Maybe this > view will give you a better idea: > http://tonycooper.smugmug.com/photos/651842312_45qoh-L.jpg > > Note the ejected shell above the rifle. Yes! Nice shot. And it certainly looks like the same rifle.
From: Bill Graham on 29 Sep 2009 00:55 "Bob Larter" <bobbylarter(a)gmail.com> wrote in message news:4abf7676$1(a)dnews.tpgi.com.au... > Bill Graham wrote: >> >> "Bob Larter" <bobbylarter(a)gmail.com> wrote in message >> news:4ab33be9$1(a)dnews.tpgi.com.au... >>> Bill Graham wrote: >>>> >>>> "wrbrown13" <wrbrown3(a)bellsouth.net> wrote in message >>>> news:xz99h2s243hc$.9skloajqavx8.dlg(a)40tude.net... >>>>> On Thu, 10 Sep 2009 15:36:20 -0700, Bill Graham wrote: >>>>> >>>>>> "Bob G" <mrbobjames(a)yahoo.com> wrote in message >>>>>> news:adbcdb79-6c7f-4021-8fc0-3adf608d7083(a)w10g2000yqf.googlegroups.com... >>>>>>> Republicans would rather get jerked around by the corporations than >>>>>>> by >>>>>>> the government. Wait until you get a horrible diseaase and your >>>>>>> health >>>>>>> insurance company drops you like a hot potato. >>>>>>> >>>>>>> The fact is that this nation is now an oligarchy (and has been for >>>>>>> some time) and not a democracy. >>>>>>> >>>>>>> How does that go, from the corporations, by the corporations, and >>>>>>> for >>>>>>> the corporations? >>>>>> >>>>>> That is what litigation is supposed to correct.....You still have the >>>>>> right >>>>>> to sue. But I never said that government couldn't regulate. Your >>>>>> health >>>>>> insurance policy should list the stuff it doesn't cover, in large ten >>>>>> point >>>>>> type.......I would vote for a law like that. >>>>> >>>>> >>>>> Now there's a thought. Sue a large corporation who has any number of >>>>> lawyers on their staff and can drag litigation out intil you don't >>>>> have a >>>>> penny to your name. Great in theory, but a joke in reality. >>>> >>>> They usually settle out of court. Why? Because juries are very >>>> sympathetic to the little guy, and have been known to award many >>>> millions of the big companies money to him. >>> >>> After years of litigation, during which the plaintiff may have died of >>> their illness. >> >> Better yet....Then his poor widow collects even more money.... > > Gee, I'm sure that's a huge comfort to her. It's the front page news that the, "big insurance companies" are afraid of......
From: Chris Malcolm on 29 Sep 2009 06:28 In rec.photo.digital.slr-systems Neil Harrington <secret(a)illumnati.net> wrote: > "Chris Malcolm" <cam(a)holyrood.ed.ac.uk> wrote in message > news:7i8u6lF30hncfU1(a)mid.individual.net... >> In rec.photo.digital Neil Harrington <secret(a)illumnati.net> wrote: >>> Chris Malcolm wrote: >>>> In rec.photo.digital D. Peter Maus <DPeterMaus(a)worldnet.att.net> >>>> wrote: >>>>> No one has ever said that the bumblebee can't fly. Clearly it >>>>> can, it happens every day. Science has never been so blind as to >>>>> make such a claim. But what Science HAS said, is that the bumblebee >>>>> is UNSTABLE in flight, an aerodynamically unsound design. This >>>>> doesn't mean or even imply that it can't fly. Just that there would >>>>> be easier and better ways to achieve flight. >>>> Not so. What science said until recently was simply that according to >>>> our understanding of fixed wing aeroplane flight the bumblebee had >>>> insufficient wing area to fly. [snip] >>>> Not that it was unstable. It is in fact >>>> unusually stable in flight due to its relatively low centre of gravity >>>> and large effective dihedral. [snip] >>> I don't believe dihedral has anything >>> to do with it. >> >> I didn't say it had anything to do with the claim of bees not being >> able to fly. You raised the red herring of that claim having something >> to do with stability. > No, that wasn't me, that was Peter. I don't believe bumblebees either have > or require stability in the sense that fixed wing aircraft do. You're quite right, I should have checked the headers. [snip] >> Given a bee's >> bent and rather unaerodynamic shape, and the fact that it flies with >> its undercarriage down, it would be hard to decide what the >> longitudinal aerodynamic axis of a bee's body in flight actually >> was. The bee wing angle of attack varies all the time as the wing >> moves. But what the angles are doesn't matter. All that matters for >> dihedral to work is that lift is being generated by wings. It doesn't >> matter how. Since bees do actually fly then lift is obviously being >> generated therefore dihedral effects occur. > I still don't believe that dihedral has anything to do with it. As long as > the bumblebee can produce thrust, which obviously it does, and > instantaneously direct that thrust as required to either move or stay in > position, it shouldn't need dihedral or anything else for stability. > Consider the Harrier, for example. When it's hovering its wings (which don't > have dihedral anyway, they have pronounced anhedral) aren't doing anything; > the aircraft is just sitting on its thrust. I think that is basically what > the bumblebee is doing. Like many fighter aircraft the Harrier has anhedral so that when in rapid forward flight it can use the instability to increase the speed with which it can change direction. It's too unstable for purely human control, and relies on assisting the pilot with high speed computer control to make it manageable. When hovering it is sitting on the thrust produced by its engines, and is getting no lift at all from the wings. So the stability of the Harrier's hovering depends entirely on how the direction of the thrust is controlled. Sitting on top of downward thrust is akin to balancing a pole. It's basically unstable and continuous correction is needed to maintain stability. In the case of the Harrier controlling the orientation of the downward thrust is too fast and critical for a human pilot to control and needs high speed computer control to maintain stability. Whereas the bee when hovering is still deriving its lift from the wings in exactly the same way as it does in forward flight. In that respect it's more like a helicopter. So in the case of the bee the effective dihedral of the wings combined with its low centre of gravity gives a basic stability to the system. Unlike a modern fighter aircraft the bee is rather low in computational power so has to rely more on inherent stabilities. Since it's also more of tanker than a combat aircraft in design it can afford the consequent trade of high speed manoeuverability for stability. >>> I'd still like to know where the original "insufficient wing area" story >>> got >>> started, though. Absent some proof of a serious scientific analysis in >>> the >>> past claiming that, I'm inclined to believe it may be more of an urban >>> myth. >> >> It has been difficult to track down the source of the claim. According >> to Wikipedia the earliest published claim comes from the introduction >> to "Le Vol des Insectes" in 1934 by the entomologist Antoine Magnan, >> who was relying on unspecified calculations done by his assistant >> Andre Sainte-Lague. >> >> But the story was verbally current long before that publication. >> >> What Wikipedia says about that is that >> >> "Some credit physicist Ludwig Prandtl (1875-1953) of the University of >> Gottingen in Germany with popularizing the myth. Others say it was >> Swiss gas dynamicist Jacob Ackeret (1898-1981) who did the >> calculations." >> >> and more generally >> >> "It is believed that the calculations which purported to show that >> bumblebees cannot fly are based upon a simplified linear treatment of >> oscillating aerofoils. The method assumes small amplitude oscillations >> without flow separation." >> >>> It's a popular one anyway, and will probably go on forever -- like the >>> widely held belief that before Columbus everyone thought the earth was >>> flat. >> >> Such beliefs would soon die out if we gave our children a better >> scientific education. The problem is that a lot of people, especially >> in the US, think that our children are already being exposed to too >> much science, > I've never heard anyone make that complaint. I should have been more explicit. I meant too much science compared to religion. There are for example a number of religious Americans in Britain who are trying to persuade us that we are teaching our children too much science and too little balancing religion. One of the dangers as they see it is that with too much science and too little religion the children might end up believing in Darwinian evolution. > The problem in the U.S., I think, is that much of our primary education is a > waste of time and money. We have some very good schools but apparently a lot > more really lousy ones. I have read that young people going from high school > into the armed forces (which you would expect high school to be enough to > prepare them for) often have to be given remedial education on entering the > service, before they can be trained to actually do anything. And I know for > a fact that our local community college -- and presumably all community > colleges in the state -- routinely gives new students, who of course have > graduated from high school, a fairly simple reading comprehension test to > see whether they require remedial education in English before they can do > anything else. You're right of course that poor schooling is a major problem. In the UK our major problem seems to be the increasingly bad behaviour of problem children, which means that higher staff-student ratios are required to stop the bad behaviour from making the class impossible to teach. > What is a factor is the problem of teachers' unions, which make it > impossible to get rid of worthless teachers. Also, again in the inner > cities, is the really big problem of lack of discipline. Where the teachers > are afraid of the students -- often with good reason -- the schools are > unlikely to produce well-educated graduates. We have the same problems in the UK. >> The "according to science bees can't fly" is a very popular >> simple way of explaining to ignorant gullible people why they >> shouldn't trust science. And so long as plenty of people are making >> plenty of money out of encouraging people to distrust science it's >> bound to go on. > Yes, but that is true even among some well (or at least expensively) > educated people. I think you're talking about people who have had a good education which included very little science. Not only is that a problem in the general population, it's a very serious problem with politicians now that our highly technological civilisation is not only capable of providing a completely artificial lifestyle to city dwellers, but is affecting the life supporting conditions of the entire planet. -- Chris Malcolm
From: tony cooper on 29 Sep 2009 07:27
On Mon, 28 Sep 2009 23:44:17 -0700, "Bill Graham" <weg9(a)comcast.net> wrote: >Be sure to write the first time you encounter a CHP officer with your >idea that you have an inherent right to carry a concealed weapon >without a permit. I'd be interested to see how that plays out. > >I have spent many happy hours arguing exactly that with California Police >officers......My wife's grandson-in-law happens to be one. In many cases >they agree with my position on the matter. This is the ChrisH School of Reasoning. If you know one person who shares your opinion, that means "everyone" agrees with you. -- Tony Cooper - Orlando, Florida |