Showing posts with label real time. Show all posts
Showing posts with label real time. Show all posts

3/16/2008

Mail-to-GE; Mail-to-Map service

Eugene Potapov

View Larger Map

View in Google Earth
Mail to Map/SMS-to-Map/Mail to GE service: new twist in (r)Evolution

The idea of creating a simple “Mail-to-Map” service came when I was tracking White-Tailed Deer in the suburbs of Pennsylvania. The GPS coordinates were send by the collared deer as a SMS/Text Message via GSM/cell-phone networks to a server in Sweden, and then relayed to my e-mail account. I was surprised to find out that there was no way for me to gain access to the server, so the creation of dynamic kml/kmz files straight from the server was out of the question. All what I was left with was a set of e-mails with 8 coordinates in each.

Here is my first attempt for a solution, which reads coordinates in e-mail and relays coordinates in real-time to the Google-Earth/Google Map service. I believe this is the fist successful solution of Mail-to-Map service which is based entirely on free web services. Let me know, if it is not correct.

Important notice: since the displayed coordinates belongs to a live animal (currently a white-tailed Deer nicknamed Thor), by reading this page and looking at the map you are accepting terms of agreement: “do not harm the animal in anyway’. Actually it lives on private grounds or a preserve territory anyway.

So, if you want to see the resulting dynamic map, skip this section and click at the map links or download the kml file.

If you are interested in details, here they are.

1. Set up a blog dedicated exclusively to ‘mail-to-map’ service. There are number of possibilities for doing that. For this project I used http://u-mail-to-map.blogspot.com/ Be sure that the blog is set for only for you to edit.
2. Set up e-mail address within blog setting, so that you can e-mail the data to the blog. Use this e-mail address for the step 3.
3. Set automatic mail forward to the e-mail address set in the step 2. I use g-mail account with associated filters to forward only messages referred to particular collar (individual) number.
4. set up a spread-sheet in google-documents and link the blog to the spreadsheets. I use command “=importxml("http://u-mail-to-map.blogspot.com/","//p[1]/text()")”. The resulting spreadsheet is here: http://spreadsheets.google.com/pub?key=pb-UYBP_92h9qQKwbVy07Zg&gid=0
5. Consult google-spreadsheet documentation how to filter/sort the location, and this posts ( http://bbs.keyhole.com/ubb/showflat.php?Number=725524 ; http://bbs.keyhole.com/ubb/showthreaded.php/Cat/0/Number/550183 ) how to construct kml files from the spreadsheets. Mind, that if the coordinates are ‘blank’, the google-maps/google-earth service will treat such locations as ‘syntax error”. In my spread-sheets I corrected “GPS timeouts” by substituting “blanks” with average locations for entire sms message (8 gps fixes).
6. Now link the kml portion of the spreadsheet (http://spreadsheets.google.com/pub?key=pb-UYBP_92h9qQKwbVy07Zg&gid=4&output=txt&range=Q2) to google maps (example here), and create “Network link” as advised in this post (). The resulting KML file is here. Do not forget to “publish” the spreadsheet, and tick the widnow “Automatically re-publish when changes are made”. The address “pb-UYBP_92h9qQKwbVy07Zg” is unique for your spreadsheet.
7. Now, important notice about refresh rates. In my example the coordinated arrive via email every 40 min, blog is updated almost instantly, spreadsheets are updated/re-published c. every 5 mins, but I have notice that it may be as long as 20 mins on some occasions. So it is prudent to set refresh rate to 20-40 min in the network link, so it will deliver the up-to-date coordinates.
8. For web-pages and imbedded iframe links: it is important to set “No-cache” options, and refresh rates. I used all possible solutions to make the web page browser independent:
meta equiv="CACHE-CONTROL" content="NO-CACHE"
meta equiv="PRAGMA" content="NO-CACHE"
meta equiv="Expires" content="0"
The last tag was instrumental to tame IE.
Refresh rate was set to 900 sec by the command
meta equiv="Refresh" content="900"
Failure to set auto-refresh and no-cache options will result in displaying out-of-date locations.
Important is to center the map on your coordinates. I achieve it my pointing g-maps to get ll from the cell in my spreadsheet: “ll=http://spreadsheets.google.com/pub?key=pb-UYBP_92h9qQKwbVy07Zg&gid=1&output=txt&range=G2”.

The resulting Google-Map is here http://www.potapov-nature.com/forBA/deer/map4.html , and kml file (network link) for Google-Earth is here.
A block diagram of the totally free web based Mail-to-Map service is below.

Potentially such simple Mail-to-Map solution can be used for a variety of applications such as satellite telemetry, fleet monitoring, iphone coordinates display, sms-to-map service, etc.

6/09/2007

Rain rate. Time animation.




View as slide show http://www.flickr.com/photos/valery35/sets/72157600327956879/show/

Download KML network link

TRMM_3B42RT_3H
Network link to time animated Rain rate (mm\hr).
WMS+Spreadsheets.

This updated now by refresh of spreadsheets and not need edition.
Shift of time: 12 hours
Step: 3 hours
Time of interests: 3 days (np make more)
List of images updated automatically every 5 min!
By animation you can uses cursor width = 3-6 hours.

Spreadsheets: http://spreadsheets.google.com/pub?key=phRmoRD2Q-V9L8erXf9vCLA

Credits:
http://disc2.nascom.nasa.gov/Giovanni/tovas/realtime.3B42RT.2.shtml#description
http://disc.gsfc.nasa.gov/services/wxs_ogc.shtml

Quote:

Experimental Real-Time TRMM Multi-Satellite Precipitation Analysis (TMPA-RT):

Why Study Tropical Rainfall?

The Tropical Rainfall Measuring Mission (TRMM) is a joint U.S.-Japan satellite mission to monitor tropical and subtropical precipitation and to estimate its associated latent heating. Motivations include:

* The tropics play an important role in the global hydrological cycle, and tropical rainfall is the critical component of this role. Three-fourth of the atmosphere's heat energy derives from the release of latent heat of condensation in the process of precipitation. Two-thirds of the global precipitation occurs in the tropics.
* The variability of tropical rainfall affects the lives and economics of more than half of the world's population.
* The large spatial and temporal variability of rainfall systems poses a major challenge to estimating global rainfall.

TRMM provides systematic, multi-year, visible, infrared, and microwave measurements of rainfall in the tropics as key inputs to weather and climate research. The satellite observations are complemented by ground radar and rain gauge measurements to validate the satellite rain estimation techniques.




4/07/2007

How to change refreshinterval on server ?

Work with the processes of real time requires the possibility to change the time of refresh on the server for all clients. This is required to carry out "in flight". Problem in the fact that networklink has already been located on client computer and we cannot it change.

I made this with use networklinkcontrol > minRefreshPeriod and propose an example of use. With one refreshinterval=1sec we see the actual time of refresh 2 and 5 sec. If we change on server minRefreshPeriod in networklinkcontrol then to all clients time of renovation also changed.

Time of refresh = min [ refreshinterval in networklink (client); minRefreshPeriod in networklinkcontrol (server) ]. We can simple set refreshinterval in networklink = 1 sec.

In KML docs i it did not find examples and publish the results of testing.

Network link
Forum

You can test this on the local computer, if you change path to KML files. On my computer this thus. You can edit minRefreshPeriod in kml files and see results.

In network links:
refreshMode=onInterval
refreshInterval=1 sec

In placemarks we add section
NetworkLinkControl and
minRefreshPeriod=5 sec and
minRefreshPeriod=2 sec