Newsletter – January 1, 2006

Introducing GPRSIM v3.0; GPR-Slice Updates

GPR-SLICE and GPRSIM Users

Best to all of you in the New Year!

I would like to welcomea new subscriber, Paul Bauman fromKomex International Ltd(www.Komex.com). Komex is a large environmental and engineering company with offices worldwide. I had met Paul several years back and had actually done some archaeological imaging for him and Harry Jol at the University of Wisconsin. Although Paul's main work at Komex is mostly in engineering applications, hehas worked extensively in Israel on archaeological surveys at Bet Sharim and Bet Shean and has used manygeophysical tools in addition to GPR.

We welcomePaul to the GPR-SLICEcommunity!

At the request of users from Lufkin Workshop, I have finally completely updating the GPR-SLICE manual. It is now available on the subscribers page of thewww.GPR-SURVEY.com, password is still "Iceland". Itis located in a single Word Document and it is close to 19 mb. InFebruary, anew password will be implementedand I will let you know then....Well, at least we haveslowed our pace down with the software to only 1 update per month!I imagine it will probably every 2-3 months in the near future.

During thethird week in December, I was contacted by 3 users, Hyundok Oh at the Korean National Cultural Properties Research Institute, Matt Barner at URS corporation, and Paul Bauman who just signed on. All were involved in GPR-GPS surveying. I reviewed some of these options with them and without sounding like a used car salesman,I have taken a quote directly from Matt's email sent on December 16,with regard to the GPR-GPS imaging options:

"Hey Dean,

Well, with some trial and error, I managed to get some good data with the
GPS and the Noggin. By streaming the GPS directly into the Noggin, you do
get the .gps file, as I suspected. This is a nice added feature.... Anyways, SLICE
worked great, and I was happy with the ease with which I could process my
GPS data. We may end up spending a good deal of time with converting final
data from UTM to State Plane, but truth be told, I am elated that you
already have the conversion to UTMs built in to the software because
Lat/Long is impossible to work with in any 2-D fashion....." Dec 16, 2005

For those that do not know, Matt was the first user to request imaging capabilities with GPS in the software. We accomplished the basic features in 2003 which was presented in a joint paper at the SAGEEP convention. Of course there have beenmore refinements since then which we will discuss shortly. I also ran some brief training over MSN messenger with Dr. Oh in Korea one evening. He was using GPR-GPS imaging for the first timewith the GSSI SIR 3000, and he was able to sync the instrument with a Trimble Pro XR GPS instrument to directly create the *.dzt.gps files required in the software. We created some images to test his GPR-GPS collection, and everything was working properly. Finally, Paul on his first introduction to software, had also collected GPS data with a SS Noggin survey. This data we also processed very quickly. Although, a format that was used in their output of the GPS file was not standard, I wrote a brief utility to convert this file to the standard *.dt1.gps file used in the software. I have not yet put this utility into the software at this time as it is probably not going to be a standard output from Noggin equipment or other equipment. In the manual on Section 8 there is a complete updated description of the formats and requirements for GPR-GPS imaging.

There is a new option for GPR-GPS imaging which is listed in the Navigation Menu which needs further discussion here. Matt, and Doria intheir GPR-GPS surveying had conditions in theirGPS files which required adifferent navigation assignment. Doria in a survey at White Sands, had recording GPS and1 second intervals while her GPR unit was in continuous recording mode. Here GPS filehad fallouts where occasionallyone ortwo seconds ofdata was missing. If any data were missing, theapplication of the Artificial Marker navigation assignment can not be used since all the GPS readings are not equidistant inscan number. Remember, inArtificial Markers we just applytag thedata based on the total number of scans equidistantly. Well,to solve Doria's problem some time ago, I told her to output thecorresponding scannumberon the radargram where the GPS reading is made. Sheluckily had included this value in the raw GPS files she made, and the copied the scan# to *.mrk files by hand into \marker\ folder for the navigation.Wenow have a utility in the Navigation Menu which will extract this from *.gps file and write it to the *.mrk file:

Clicking the GPR Trace# will take the fifth column which should now be written to contain theTrace # (scan #)in the *.dzt.gps or the *.dt1.gps for the *.rd3.gps files and it will write the *.mrk marker files for navigation. In this instance, GPS readings can in effect be made randomly in scan#. This GPS Trace # essentially treats the navigation similarly to field markers placed in by hand. Matt had found from his GPS collection with the Noggin, that some gps files had Eastings or Northings values set to 0. If this is the case, the GPS Trace # option when it is run, will have a warning message box appear for every corresponding GPS file that has this problem. Currently, we do not delete these lines from the GPS file. One will need to go into an external editor to either remove these lines, or do some kind of interpolation if they want to keep these locations. Matt had about 20 lines of GPS radargrams, and 2 of those lines had recording problems. This may be typical data quality until the equipmentmanufacturers improve the GPR-GPS connection. Just a note: theraw SSGPS files that havethe NMEA stringsoutput also has a separate line before the NMEA string that indicates the trace number for the GPS reading. TheSS to UTMutility in the Edit Info File, will automatically write the required GPR-SLICE UTM *.gps files and put the trace number into the 5th column.(Once again, for a complete description of the formats, please see Section 8 in the updatedmanual).

Anyway, I found it interesting that more users are beginning to migrate to GPS-GPR imaging and by coincidence3 different users contacted me during the same week about GPS. The other 2 users which I know regularly are using GPR and GPS are Doria Kutrubes at Radar Solutions International and Brian Herridge at 3D Geophysics. I believe any of these users would alsowelcome any inquiries regarding data collection with GPS. I am not an expert at all in the data collection with GPS as our lab in Japan currently does not even own a GPS unit. So please contact the field experts with regard to GPS collection if you have an interest. I encourage you all tobegin storing any important dialog in this regard or other useful information on the www.GPR-SURVEY.com message board and perhaps make your correspondence there if you like.. If you would like to contact any of these GPR-GPS experts regarding field surveying with GPS, I have included their email addresses here:

Doria

Dr. Hyundok

Brian

Matt

Paul Bauman <>

I just want to make a general comment. At this stage of the game with GPR-GPS imaging, although it holds a lot of promise for making GPR surveying easier, currently with the accuracy and the possibilities of data fallout, there may be degradation in thequality of GPR-GPS imagesas opposed to those that might beobtained from traditional navigation. I would very much like to see any data from users that apply both typical navigation (e.g. survey wheel or hand markers) with the resultsfrom a GPR-GPS survey to see if there is significant degradation in the subsurface imaging. We have run an experiment in Louisiana with the USFS, but unfortunately the one site where we had both navigation data, we had too many nearby trees which caused multi-pathing and we were not able to get the best possible GPS readings available.

Because of the recent interest in GPR-GPS surveying, I have placed two practice folders at http://www.gpr-survey.com/practice/named ss-gps and gssi-gps. These zip files contain GPR-SLICE v5 folders for Sensors and Software GPS examples and Geophysical Survey Systems IncGPS examples. The GPR-SLICE manual isfairly complete and one shouldread the GPS sectionsbefore practicing with these datasets. There is no separatehandouts for theseexample folders. The SS-GPS folder has initial navigation with NMEA strings listed at *.gps files in the \raw\ folder. This folder also contains the converted *.dt1.gps files made with utilities in the software. The GSSI-GPS folder just contains the *.dzt.gps files as these were the original outputs of the GPS logger which are ready to be used for processing. When one is comfortable with the information and wants to start processing from scratch, I recommend creating a new folder and then simply copying the necessary files from \raw\ folder in these example folders to the new practice folder. Hopefully you can reproduce some of the jpgs in the folders. These practice folders do not have any significant structures so do not expect any Roman amphitheatres to appear in the images! Nonetheless, I want to thank Brian Herridge and Erik Kitt from 3D Geophysics for making the SS-GPS data available to you and Matt Barner from URS corporation for providing the GSSI-GPS dataset.

Several bugs that were reportedwith GPR-SLICE.These included:

1) Improper time slice overwrite warning messaging in the Grid Menu

2) Fudicial header markers (red markers)along withthe active navigation markers (blue markers)at the same time would not display at the same time in the Show Marker option for 16 bit radargrams.

3) User Edit also did not properly show 16 bit survey wheel markers if they were inserted in the radargrams during the Edit Marker menu

4) Draw Grid # would not output a jpg or bmp, requiring the user to use the Draw Grids button

All these issues have been corrected!

Professor Udaya Halabe asked for mm units to be included in the Options menu as they are working on very fine scale GPR surveys for timber. Millimeters are now available for time scaling and labeling.

The update isavailable on the Subscribers Only page. If you have a GPR-SLICE version that was any update before Dec 1, 2005 - DO NOT RUN THIS VERSION - as you will be locked out of the software. Please update with the latest version before running GPR-SLICE. The latest executable was created on January 1st. One can always see the latest version by clicking on the Help Menu in the software to see the last date created. I have decided to not rename the version to 5.1 and have it run out of a v5.1 folder. For now, the update should be simply overwritten as usualinto the v5.0 folder. If any one does get locked out the software, please send an email I will give you instructions on unlocking the software. These added security measure unfortunately havebeen necessary because of delinquency with a few subscribers.

I have been asked by several older users about purchasing GPR-SLICE rather than subscribing. These inquiries have mostly come from Universities where budgets year-to-year are not known. Originally up until 2004 GPR-SLICE was not for sale because those thatcame into the software realized how much development was being done and it would have been unfeasible several years ago to offer and incomplete software package. Because of the great strides with the software and only occasional cosmetic bugs appear now, I can offer software for purchase to those that may need this option. The software can be purchased at 4 times your subscription cost. After the Lufkin workshop we realized that only very few users even get into all the options in the software and many have more software engine that they can handle. Many can probably survive several years or more without any additions made to the present version of the software. If you are one of those that prefer to permanently acquire the software then please contact me directly.

Upcoming events:

On January 16/17 I will be running a software training session for Geovision. Francisco Romero from Geovision in New Hampshire will be attending, as well a J. B.

Sawyer atthe mainCalifornia branchplus other employees from this geotechnical company will be attending. I will be in Los Angeles through Jan 22nd, after which I will be in Japan for several surveys. I was invited to work withthe Saitobaru Archaeological Museum on surveying the Imperial Family tombs. The tombsare believed to be the mother and father of the first emperor of Japan inHeian Period (8th century). This will be an exciting survey opportunity. Dr Yasushi Nishimurafrom UNESCO andDr. Hyundok Oh from Korea are alsogoing to participating in the joint survey with Noriaki Higashi and Hiromichi Hongo from the Saitobaru Archaeological Museum.The work in Japan will keep me there for 3-4 weeks. I do have a Japanese cell phone number which can be reached directly fromthe U.S. or Europe. My direct cell number thereis 011-81-90-1639-4434.

For those GPR-SLICE users that are also GPRSIM users, I will be emailing the new release of GPRSIM v3.0 in 2 weeks time to you.

On a special note, I want to announce the retirement of Dr. Kent Schneider of the United States Forest Service on January 3rd of this year. Kent has provided 30 years of service to the Forest Service as a Heritage manager and one who has also taken strides tofoster new technology in the government. He was one of the first to design a mobile archaeological lab in the mid 70s and was recognized by then Georgian Governor Jimmy Carter on his accomplishments. Kent was the sole energy implementing aremote sensingprogram in archaeology forthe Forest Service and he has been doing geophysics in archaeology longer than anyone that is on this mailing list! I was fortunate to meet Kent as he invited me as an instructor ata GPR workshop they were sponsoring at the University of Arkansas in 2001. Five wordscame from Kentat the end of the workshop"How did you do that?" that eventually brought this software to all of you since 2001. Kent's office took the first 2 subscriptions at his request andhe has been my mentor here in the U.S. ever since. Iwill always begrateful to Kent's help in directing me in this endeavour as well as his continued friendship. Many of youhave worked with Kent in the past and on behalf of all you as well,I want to thank Kent for all that he has done for all of you as well...