thank you sir
Posted on 02/17/2018 10:15:51 AM PST by mairdie
The approach, known as light detection and ranging scanning (lidar) involves directing a rapid succession of laser pulses at the ground from an aircraft.
The time and wavelength of the pulses reflected by the surface are combined with GPS and other data to produce a precise, three-dimensional map of the landscape. Crucially, the technique probes beneath foliage - useful for areas where vegetation is dense.
...
The team also found that Angamuco has an unusual layout. Monuments such as pyramids and open plazas are largely concentrated in eight zones around the city's edges, rather being located in one large city centre. According to Fisher, more than 100,000 people are thought to have lived in Angamuco in its heyday between about 1000AD to 1350AD. "[Its size] would make it the biggest city that we know of right now in western Mexico during this period," said Fisher.
(Excerpt) Read more at theguardian.com ...
But, today, the left shift key on my laptop's keyboard conked out -- and, it's almost impossible to do HTML coding without a left shift key! Took it to the shop, and they say they'll have it ready Friday -- if the parts come in...
I hope so: I have an archaeology paper to present on Saturday!
I'm sending this on my wife's MacBook Air. Trying to get the graphic engine/presentation software -- and my presentation -- running on it ...just in case!
Bottom line: it may be some time next week before I get the imaging series coded and uploaded -- but I'll be sure to ping all of you when it's viewable. I think you'll appreciate -- and, perhaps, enjoy -- it... '-)
My thrift shop had a basket full of external usb keyboards the other day. Too bad you don’t live here.
If you bombard a forest with a dense-enough "cloud" of laser pulses, statistically, some of them will "find holes between the leaves" and reach the ground -- and will be the last to be reflected back to the detector. By subtracting out all the "quick returns", all you have left is those that reflected back from the "bare ground".
Ideally, in a temperate area, you do the overflight in winter, when foliage is at a minimum...
But, I agree with you: getting enough pulses through a triple-canopy jungle must be a genuine challenge!
Deepest sympathies, TX. My keys get sticky but I haven’t actually lost one yet. Sounds horribly frustrating. May the technicians finish early!
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No problem. It's still under warranty, and Apple is not only replacing the keyboard, but the entire upper cover to which it is attached -- which includes not only a new trackpad, but new batteries!
Not bad for a very heavily-used, almost three (3) year old MacBook Pro...
Basically, a brand new Mac for one stuck key! '-)
thank you sir
It took me a while to come up with that simple understanding of the problem. Now, I'm working on doing an animated graphic to illustrate it -- in anticipation of an archaeology paper on the use of LiDAR to map the remains of the 1813 emigrant "road" into Texas, known as "Trammel's Trace"...
most interesting, i'd like to read it when done
:’)
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