Network corrected real-time is a technological approach to high precision GPS/ GNSS positioning that has been theorized about, studied, experimented with, and implemented in various academic, scientific, and commercial forms for nearly a decade. Many of the various approaches share the fruits of past research, algorithms, and technological tools; some which are in common.
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By the time you read this, the "switch" will have probably taken place. Part of the U.S. Air Force Architecture Evolution Plan (AEP) is to transition the aging mainframe system used for GPS ground control to a serverbased architecture. Many surveyors are probably aware that ground control segment is used to upload the almanacs to the satellites on a daily basis. I was recently invited to sit in on a teleconference regarding the AEP.
The driving force behind the migration, in addition to replacing the legacy mainframes, is the new generation of satellites, the Block IIF (F for follow-on). The IIFs have increased signal and navigation capabilities that the current system cannot implement. The AEP will allow the Air Force to handle up to 60 satellites. Currently, they are handling 31 "birds". With the launch next year of the first IIF, the number will rise to 32.
During the phone conference, the Air Force representative stressed that AEP has been underway for more than year, and that several practice uploads have taken place, as well as three rehearsals of the actual transition. Even so, part of the plan includes a reversion to the old system if problems arise. Since the satellites will continue to orbit, the switch-over, which will take several hours, is likened to changing the engine on a car that is traveling down the highway at 65 miles per hour. For security reasons, the Air Force did not announce when the switch would take place, only that it would occur in September.
Our Aging Infrastructure
Sadly, the tragedies of the weakened levees in New Orleans when Hurricane Katrina struck in August of 2005 and the August 1, 2007 bridge collapse in Minneapolis are but the tip of the iceberg when it comes to America's aging infrastructure. In the interview with the Leica Americas president Bob Williams in the October 2006 issue, I wrote at length about our Interstate Highway System and ASCE's Infrastructure Report Card. While most of the categories received grades of D, bridges received a grade of C. What conclusions might be drawn from those scores?
A New Writer Where do you stand on GIS? Opinions are all over the board. Personally, I believe the main reason why many surveyors have "turned their backs" on GIS is because they have no desire to be associated with lower-accuracy work, and because they do not wish to be engaged in massive amounts of mapping based on lower-accuracy data. But how do you, as a survey practitioner, handle record-keeping and previous jobs? When the call comes in, do you rely on institutional knowledge of the fact that you have worked in an area? Do you keep these records on a map or in a map book? Do you hit the filing cabinets? Suppose you had a digital system that you could call up at a moment's notice a system that shows prior work, control monuments, and other important information needed to do new work in an area. What if this system also included information about job status, billing, and everything else you need to successfully execute a job? Surveyor Robert Young has such a system, and it has made his business more efficient and more profitable. We welcome him as a new writer this month with the first in a series of articles that will explain how he has used GIS to make his staff's life easier and his company more productive.
Marc Cheves is editor of the magazine.
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Editorial: Machine Control Redux
I have received a fair amount of response to my July editorial about machine control. Responses included those who agree with me as to the inevitable impact it will have on the future of surveying and those who accuse me of selling out. Notwithstanding those states such as California that require a .... Read the Article
Point to Point: The Pincushion Dilemma
Pincushion corners result when two or more markers exist identifying the same property corner. If set by surveyors, they are invariably the result of different interpretations of evidence, whether justified or not. The measurati have almost universally denounced them as further evidence of rank-and.... Read the Article
The WowFactor: OfficeSync
Drastic changes in the U.S. economy, including the recent runup in the price of gasoline, have had a direct effect on how firms use technology to remain competitive. Civil engineering and land surveying firms have had to make serious decisions, and time management is ... Read the Article
In Search of Monhegan's Letters
Monhegan Plantation is an island ten miles off the coast in the Gulf of Maine. An artists' haven with a rich history in fishing, the island's average population of 75 residents explodes each summer with the opening of ... Read the Article
Towers of Power - Surveyors Locate Next Generation Transmission Lines
As originally planned, the Eastern Plains Transmission Project, one of the country's largest power expansion projects in progress, is expected to ultimately deliver about 1,000 miles of .... Read the Article
A Visit to the South Carolina Geodetic Survey
One of the hold-ups in the implementation of Real Time Networks (RTNs) for machine control has been the vertical accuracies. That being the case, when one of our writers, Joe Betit, told me that he had heard that the South Carolina .... Read the Article
In Memoriam: John E. Chance, 1924-2008
A legend within surveying circles along the Gulf of Mexico and in the petroleum and pipeline industries worldwide, John Chance died May 1, 2008 at his home in Lafayette, Louisiana. "Mr. John," as he was affectionately known by his friends, was born John Edward Chance on ... Read the Article
FeedBack
More on the Schuylkill Center Wendy Lathrop's valuable article "Where There's a Will... " [Sept. 2007] couples the Orphans' Court activities of the Barnes Foundation and the Schuylkill Center for Environmental Education (SCEE). From a legal point of view the breaking of ... Read the Article
Software Review: General CADD
Backward compatibility has always been one of the things that make a good solid product. General CADD started out as an inexpensive CADD program working in DOS. Generic CADD was the name and it made it possible for surveyors who could not afford the very... Read the Article
Survey Reports: Preparing a Survey Report - Part 4: FAQ
This is the fourth article in a series of articles suggesting formats and contents of a survey report. Previous articles dealt with opinions on the location of corners and boundaries [Feb. 2008]; encroachments, gaps and overlaps [Mar. 2008]; and limitations of of the surveying ... Read the Article
Vantage Point: Water Over the Dam and Down the River
What's old is new, and it's all wet. It may seem to be a "modern" approach to look beyond our own municipal boundaries to see what is happening on the other side of an invisible jurisdictional line that will affect flooding and stormwater on our side of that line. But awareness of ... Read the Article
• 15th Annual GeoTech - October 7-8, 2008, NOAA’s Auditorium and Science Center in Silver Spring, MD. Hosted by Potomac Region of the American Society of Photogrammetry and Remote Sensing and co-hosted by the NGS, 1 day of Workshops taught by experts, and 1 day of Technical sessions.,
• Geography in Las Vegas - March 22–27, 2009. Join 8,000 geographers, GIS specialists, and environmental scientists from around the world in Las Vegas for the very latest in research, policy, and applications in geography, sustainability, and GIScience, during the annual conference of the Association of American Geographers.
• California Land Surveyors Association 2009 Conference - March 28-April 1, 2009, Hilton San Diego Resort (Mission Bay).
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, (707) 578-6016.
• SPAR 2009 - March 30- April 1, 2009, Hyatt Regency Hotel, Denver, Colorado. SPAR 2009 will focus on best practices for using 3D imaging technologies to design and deliver capital projects as well as operate, modify and maintain production, manufacturing and infrastructure assets.
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