Dr Schwarz, former NGS Systems Development Division Chief, and distinguished scientist has died. I had the pleasure of working with him intermittently during the last part of my career. I remember him as a helpful, friendly, and wicked smart. I once approached him with a computation problem that had me stumped. After a brief explanation of my problem, he immediately identified my problem and solved it on the spot. He was always kind and helpful.?ÿ
This memoriam by Drs Snay and Soler recounts his significant contributions. It includes a listing of some of his significant publications. I found his "The trouble with constrained adjustments" to be one of my favorites.
Thank you for sharing.
?ÿ
GeeOddMike,
Thanks for sharing. I never met him but have met both Drs Snay and Soler. Dr. Soler was honored at the UESI/Cal Poly Pomona Conference in 2018 and he shared some of his works with us. Brilliant minds!!
Just curious, did you once live in the Carmel Valley area of California?
Sorry to here this. I met Dr. Schwarz back in 2007 in Silver Spring MD. He was certainly a huge contributor to the science of geodesy.
RIP
Like Dr Schwartz, both Drs Snay and Soler have made notable contributions to geodesy and to the surveying world.
Thankfully, during my working life I encountered many more friendly and open people of high accomplishment than equally accomplished jerks. Working with academics I found the proportions somewhat different.
While I have worked from San Ysidro to Crescent City, I have never lived in California. The ocean front areas of Carmel area are certainly beautiful.
I never met him, but we had quite the correspondence going when he was developing OPUS-RS. I had stumbled across some information about the OPUS-RS beta test site, so I started submitting some of my files. He found out about it an emailed asking how I had heard about it and what was I doing. I explained I was just experimenting and he asked if I wanted to experiment more. Over the next year or more he sent me beta OPUS-RS (RSGPS) executable files and instructions and I loaded the various versions on my PC and proceeded to experiment. I found multiple ways to make it not work and found out when and what kind of data was not acceptable. I am rather reliably sure that some of the final user aspects of OPUS-RS were at least spurred by my tests and findings. Early beta OPUS-RS would accept submissions of 5 minutes to 4 hours. I showed that throughout a 24 hour day there were sufficient 15 minute intervals were satellite PDOP was at a higher value than allowed for a good solution. Even with our full constellation today one can still find a few higher PDOP periods during the day. At the other end I surmised that the single atmospheric model correction value they were using was not as adequate as recalculating a correction value for shorter sub periods. I belief that had some affect on their current 15 minute to 2 hour file limitations. Because RSGPS allowed me as the user to adjust certain assumed input limits and constants, I managed to blow up some final solutions. I believed that ability amused Dr. Schwarz. I also had the ability to look at the solution process as it progressed and was amazed that the RSGPS program could sometimes resolve 100% of all ambiguities with as little as 4 seconds of data. For the majority of my test solutions I was relying on NYDOT network CORS stations and had a large enough network to test solutions with primarily N-S or E-W networks and found no significant differences.?ÿ
We also discussed L1 only OPUS solutions, which I thought RSGPS was entirely capable of doing. After Charlie fully retired their was no individual with sufficient impetus to move that project further along. Also other staff persons where not inclined to humor me with later copies of RSGPS. After Charlies retirement I did manage to prove to myself L1 only data was adequate by taking L1 receiver RINEX files and calculating L2 appropriate values and then submitting to OPUS-Rs for solutions, but I never got around to automating that process.
I will miss his stimulating interest.
Paul in PA
My experience with working with NGS geodesists versus academia has been quite similar. I have seen some pretty ugly encounters when two academic researchers are in the same room vying for the same piece of the funding pie.
My "I've made it moment" happened a couple of years ago when I went to dinner with several NGS geodesists. Chief Geodesist, Dan Roman, drove us to the restaurant and I sat behind him. Upon arrival, I discovered the door would not open from the inside (could have had the child protection lock on) on the rental car, so Dan got out and opened the door for me. I immediately said "that's it, I can retire now. The NGS Chief Geodesist is chauffeuring for me!" All of the ones I have met have been great people and excellent to work with.
