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From: Jerry Avins on 29 Dec 2009 23:43 Randy Yates wrote: > Randy Yates <yates(a)ieee.org> writes: > >> John Monro <johnmonro(a)optusnet.com.au> writes: >> >>> Randy Yates wrote: >>>> "steveu" <steveu(a)coppice.org> writes: >>>>> [...] >>>>> Any sufficiently large object is not going to fall down a small hole. I >>>>> think reasonableness of size is implicit in the argument. >>>> A two-foot diameter would require a lip size of about 5 inches. Is that >>>> unreasonably large? It doesn't seem all that unreasonable to me. >>> It makes the cover twice as heavy. >> Well, not TWICE as heavy, is it? First, there must be some lip, so we >> should be comparing the difference between minimal lip and big lip. >> Second, it wouldn't be the same thickness as the center portion. >> >> Assuming the center is 1 foot radius, the little lip is 0.1 feet and the >> big lip is 0.5 feet, and the lip thickness is 1/2 the center, we'd come >> up with a ratio of 1.625/1.105, or 47 percent heavier. If I did my math >> right... >> >> Yeah, that's significantly heavier, but it's not the slam dunk Steve >> was making it out to be, in my estimation. >> >> Anyway, this seems ever more so to support my point that it is weight >> (and material and cost), not geometry, that decides this. > > I should say, "..., not hole-fall-through-ability"... Let's ask the guy down in the hole how important it is that the cover not fall through. :-) Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
From: steveu on 30 Dec 2009 00:08 >Look in any IEEE transactions and you >will find good papers mixed with papers on marginal extensions to >theory blown up to huge proportions. Hey, don't knock the papers that document a marginal extension to something. We can't all break new ground like Claude Shannon (who had a PhD before he did his ground breaking work) or Charles Kao (who didn't). Most things *are* just minor extensions of existing stuff, and its no bad thing. That's where the vast majority of progress comes from - tiny little mole hills piled up into mountains. Steve
From: HardySpicer on 30 Dec 2009 00:37 On Dec 30, 8:27 am, glen herrmannsfeldt <g...(a)ugcs.caltech.edu> wrote: > Eric Jacobsen <eric.jacob...(a)ieee.org> wrote: > > (snip, someone wrote) > > >>> I was talking to a power electronics lecturer from a reasonably > >>> good university in the UK recently. He told me only two courses > >>> in their entire electronics degree program now have any practical > >>> content. For everything else, the only lab is Matlab. > > (snip) > > > I can't imagine an EE degree without the hands-on lab stuff. How do you > > make people responsible for building stuff safely if they're never > > allowed to see for themselves what the issues may be? > > I am not so sure how it works in EE, but in physics there are > theoretical and experimental physicists. Many good theoretical > physicists aren't very good at lab work. There is the well known > "Pauli effect" http://en.wikipedia.org/wiki/Pauli_effect > Engineers haven't realised this yet. The industry ones bleat on and one about how they are the only ones that can solve real problems and the academics bleat on and on about the limitations of industry. There is little respect of one wrt the other as you can see.
From: HardySpicer on 30 Dec 2009 00:46 On Dec 30, 9:28 am, Rune Allnor <all...(a)tele.ntnu.no> wrote: > On 29 Des, 20:44, HardySpicer <gyansor...(a)gmail.com> wrote: > > > On Dec 29, 8:26 pm, Rune Allnor <all...(a)tele.ntnu.no> wrote: > > > > Again, *first* earn the privilege; *then* recieve ranks > > > and titles. Ceremonies are nothing but voodoo and mysticism > > > that have nothing to do with engineering. > > > > Rune > > > You are missing the point. A Ph.D means you have particular training > > in an area of research and that you have contributed to knowledge in > > that area. > > No, it doesn't. > > That's what everybody *think* it means, and it might even have > been true some time in ancient history, but it is not true now. > > My own thesis fails your proposition simply because everything > I did had been done before. I assembled a number of DSP methods There's an old Scottish saying..never wash your dirty knickers in public! Of course there are some Ph.Ds which are marginal. Some are more application based in engineering with little theory other than existing theory. However, a good engineering School will be looking for some form of real contribution to knowledge. It may be small but it has to be there! To make sure of this we have an external from the same country and one from a different country as well as an internal. On top of that the student must present early findings to a panel where everybody in the dept is invited. That's how it's done in NZ at least. If you don't have anything new you will be found out. However, usually publishing peer-reviewed papers is taken to be proof of an original contribution. You can usually get away with applying new theoretical ideas of others to an advanced problem in engineering. For example, applying (at the time0 H infinity control to stability of a fighter jet would be ok! Usually a small theoretical contribution would not go amiss either. Hardy
From: HardySpicer on 30 Dec 2009 01:06
On Dec 30, 4:22 pm, robert bristow-johnson <r...(a)audioimagination.com> wrote: > On Dec 29, 2:17 pm, HardySpicer <gyansor...(a)gmail.com> wrote: > > > > > Lot of truth in that re bogus outputs. Multiple outputs of the same > > thing in many cases re-worded and sometimes not even re-worded! > > Yes, new journals do spring up to serve the tenure thing and so on and > > so on. For all that though, the academic system - peer-reviewed > > system is the best we have to date. > > i actually think that the academic system that preceded the present > one, say ca. 1930, was better as a system. PhDs should be very rare > and very special. no one should be getting a PhD unless they > contribute to the body of knowledge stuff that is *novel*, I think you have rose tinted idea of the 1930s. Of course there were great Ph.Ds about then and there still are. There are Ph.Ds that do incremental work (esp in Chemistry) and others which are more revolutionary. Sometimes the good work happens several years after the Ph.D. Many people look back and don't boast much about their Ph.D. It's what you have done since that matters. As somebody else pointed out, the Ph.D is just the starting point in an academic career. Look at the discovery of DNA. This is a good example that took place in the early part of the last century. The fitting together of a jigsaw puzzle. The person who did the real science was a woman who got hardly any credit till now. She did the basic lab work on x-ray crystallography. She didn't fit all the pieces together. Crick and Watson did. Does anybody know what any one of the 3 did their Ph.Ds on? I don't and I bet it wasn't that brilliant either. Ditto for the inventors of the transistor. The Ph.D provided the basic foundation for them to carry on and do better work. Likewise for engineers in industry. A great many may well have scraped by and just passed but gone on to be brilliant engineers. (some may not!). There were some good things about that time however. Not so much pressure to produce endless publications. Quality rather than quantity counted. Less people went to University then - was that a good thing? I don't think so. Often people with money were the ones who went to Uni and the very best with Scholarships. The rest could whistle. So much more could have been accomplished - maybe those people who never made it to Uni could have done great things. Things happen fast nowadays. You have to have the paper 'camera ready" and submitted on-line. No typing with golf-ball typwriters and the like and mailing your paper abroad. by the way - Widrow was an academic who has achieved great things in DSP. He even invented the basis for the Neural net. Great man and an American too. Hardy |