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Comment Re:Hmm.... (Score 1) 13

Your comparing car apples to satellite apples. Give a read of the paper and you will see that for Dynamic World, every Sentinel 2 image comes into Earth Engine automatically and the processing is applied automatically for that image fairly quickly if the image is cloud free enough to process. The user of the Dynamic World image collection can select which images are used to make up a mosaic. Streetview is totally different.

From the Dynamic World catalog page: https://developers.google.com/...

> Dynamic World predictions are available for the Sentinel-2 L1C collection from 2015-06-27 to present. The revisit frequency of Sentinel-2 is between 2-5 days depending on latitude. Dynamic World predictions are generated for images for Sentinel-2 L1C images with CLOUDY_PIXEL_PERCENTAGE = 35%. Predictions are masked to remove clouds and cloud shadows using a combination of S2 Cloud Probability, Cloud Displacement Index, and Directional Distance Transform.

Comment Sources of AIS errors (Score 1) 194

Last week, I put together a quick write-up of the possible sources of trouble for AIS messages. It doesn't go into the needed depth on topics, but I would appreciate technical feedback and any links to people doing deep dives on any or all of the issues.

GPS spoofing possibly seen in AIS data: http://schwehr.blogspot.com/20...

And before that I've written quite a bit on the insanity that is AIS:

AIS Integrity and Security - Part 0: http://schwehr.blogspot.com/20...

Comment Nice to see some of my work (Score 1) 33

It's nice to see some of my work come to light. I created prototypes for this back a few years ago with Google Earth and GDAL for the Bathymetric Attributed Grids (BAG) file from Hydrographic Surveys... http://youtu.be/7fOTlqqQ5O4 Or build a visualization yourself using the code: https://github.com/schwehr/bag-py

Comment Documentation (Score 1) 332

Do whatever you can. Documentation, packaging, training, whatever

Consider even just small steps... e.g. posting small examples of using FOSS can help a lot. I use my blog to help NOAA accomplish its mission indirectly. One instance is how to use QGIS to read data directly from a PostGIS database:

Using QGIS to view PostGIS data

Now, how do I convince the NOAA IT folks that QGIS should be on more peoples machines?

Comment Similar question - Nautical Publications (Score 1) 328

I've had a similar question for Hydrographic Offices in various countries that have to produce Coast Pilot/Sailing Directions documents. Except in their case, this is a document that has 100+ years of revisions and is looking to 100 more years. How do we get them into a process where they can track all the changes and reference where material was submitted from?

I tried to think through some of the options for this kind of stuff here:

Managing distributed XML document editing for nautical publications

Comment Verizon's EVDO (Score 2, Informative) 199

I use Verizon's EVDO and am not very satisfied. I uses two mac laptops (ppc and x86) and suddenly started seeing a ton of kernel panics, where I had got years without trouble. The connection client is really lame. Also lame is the 5GB limit for the "unlimited plan". At least now they will not disconnect you if you hit 5GB in one month. They will "just" limit your througput. I'm out in NH and the service is come and go as with the verizon voice coverage. In San Fran, the coverage and usage was excellent. I used it on trains going through tunnels without trouble. It's annoying to have this adapter hanging off the side of the laptop all the time. Also, once in a while the network flays on "re-registering" and it locks me out of the system for 3-6 hours while the network thinks that I am trying to connect from two machines at the same time. They say that it is only for standard web browsing only. I haven't tried skype, but ssh, irc, and all http(s) all work fine. This sumer, I will also be getting a DSL or Cable link, cause I can't take this much longer as my only connection. Sometimes at my house, I get 3 "bars" and other times I go hours with none. I wish this client would log signal strength so I could see if there is some pattern to the outages. Tech support has been responsive, nice, and more friendly than most. Still, it is easy to run past their knowledge of how the network works. Over all rating: so-so

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