Joined: Thu Aug 04, 2011 8:35 pm Posts: 4707 Location: Cardiff, Wales
one topic that appears to have fascinated early science fiction writers is that of moving walkways, as stories by HG Wells, Robert Heinlein and Isaac Asimov testify
true that these days we do have some sort of moving walkways to alleviate the effect of long walking distances in airports, or in underground corridors for tube stations, but as far as i'm aware none of them have adjacent strips of different speeds - the reason for this probably being that it might be a major source of accidents and injuries
so is it likely that moving walkways, either of the SF or of the current variety, become a major feature of our megacities ? for the time being i don't see any sign of such a development, so my idea is that apart from a few restricted applications, moving walkways will remain fiction - not because it can't be done, but because it's either impractical or because most people either like to walk as a leisure activity, or prefer other means of transport as being more suitable in a city environment
Well, if were talking about Sci-Fi transport, I want a genetically engineered giant riding python. Something like a Titanoboa. A robotic version would be acceptable as well.
While there is no great challenge to walking along a level surface, hence moving sidewalks will probably never become a widely used regular feature, a currently common use for inclined transport is the escalator.
_________________ It is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence. -W. K. Clifford-
Too impractical. City design is too dynamic, in that leave a city for a decade and return and it will almost certainly have been given a face lift, some buildings uprooted, others planted, road directioms changed. The static nature of moving walkways would be unable to keep pace, I think. Altjougj I do appreciate those at my local train station and they always remind me of the termination of transcription.
I once had a lecturer, Dr. David Boam, probably the best lecturer I ever had, who likened the way in which Rho factor appears to futilely 'chase' RNA polymerase during prokaryotic transcriptional termination - to walking in the opposite direction to the movement of an escalator. He joked that one day he would find a bunch of us students walking up a downward-moving escalator and that our alibi would be that we were 'performing a scientific experiment'.
Rho binds to RNA and then uses its ATPase activity to provide the energy to translocate along the RNA until it reaches the RNA-DNA helical region, where it unwinds the hybrid duplex structure. RNA polymerase pauses at the termination sequence, which is because there is a specific site around 100nt away from the Rho binding site called the Rho-sensitive pause site. So, even though the RNA polymerase is about 40nt per second faster than Rho, it does not pose a problem for the Rho termination mechanism as the RNA polymerase allows Rho factor to catch up.
I still plan on doing it one day, just then I can tell people, 'Dr. Boam told me to do it.'