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INFRASTRUCTURE

INFRASTRUCTURE

 

The sky isn’t falling but some of our bridges are. About seventy thousand of them are structurally deficient, and about a quarter of those could go at any time. Calamities are sure to mount if nothing is done. The number that will occur (e.g., after belated prevention efforts) is unknown.


That number could be reduced by a method not currently in use. In combination with other steps (placement of sensors at strategic locations on a structure) a historical pattern of deformations can be generated automatically. The means of analyzing the deformations has already been shown to provide early warning capability, via application to data recorded before the 2011 Tohoku earthquake. There is no need to repeat the description here; it’s already documented .


Sooner or later another subject comes up: The “C” word (cost). Aside from severity of the problem, about the only other item prompting agreement is the notion that a solution is unaffordable. Let me change that notion this way: if a complete solution is deemed unaffordable, a partial solution doesn’t have to be. Prioritize . Bridges exhibiting the most urgent warning signs are highest priority for remedial action. At 1/70,000th of the total cost, no one could reasonably refuse to fix one that must be fixed.


An acknowledgment: the argument just cited is overstated. Initial investment is always a greater fraction of the long-term total, and applying a method for the first time to any operation requires ironing out some wrinkles. Still, admitting that a fraction exceeds 1/70,000 doesn’t constitute a shocking confession. The sensors don’t have to be top-of-the-line. If the “bottom line” is all that matters, then here’s the real bottom line: Their cost, plus the cost of a government-sponsored project, pales in comparison with losses resulting from a bridge collapse — let alone the losses incurred from  seventy thousand collapsed bridges. 

By James Farrell 09 May, 2023
A look back in time by James L Farrell, PHD - 2023
11 Apr, 2020
Apologies for little posting lately. Much activity included some with deadlines; this will focus primarily on the few years leading up to Covid.
11 Apr, 2020
GNSS Aided Navigation & Tracking
By James Farrell 30 Aug, 2018
Apologies for little posting lately. Much activity included some with deadlines; this will be limited to the past twelve months. In 2017 my involvement in the annual GNSS+ Conference again included teaching the satnav/inertial integration tutorial sessions with OhioU Prof. Frank vanGraas. Part I and Part II are likewise being offered for Sept 2018. Also...Read More
28 Jun, 2018
Once again I am privileged to work with Ohio University Prof. Frank vanGraas, in presenting tutorial sessions at the Institute of Navigation’s GNSS-19 conference. In 2019, as in several consecutive previous years, two sessions will cover integrated navigation with Kalman filtering.  Descriptions of the part 1 session and part 2 session are now available online. By way of...Read More
30 Apr, 2018
The Institute of Navigation’s GNSS+ 2018 Conference provides me the privilege of collaborating with two of the industry’s pillars of expertise. Ohio University Professor Frank van Graas and I are offering fundamental and advanced tutorials.  Then on the last day of the conference I’m coauthored with William Woodward, Chairman of SAE Int’l Aerospace Avionics Systems Division and hardware lead...Read More
24 Apr, 2018
A new SAE standard for GPS receivers is a natural complement to a newly receptive posture toward innovation unmistakably expressed at high levels in FAA and Mitre (ICNS 2018).  Techniques introduced over decades by this author (many on this site) can finally become operational. 1980s euphoria over GPS success was understandable but decision-makers, lulled into complacency, defined requirements in adherence...Read More
22 Mar, 2018
At April’s ICNS meeting (Integrated Communications Navigation and Surveillance) as coauthor with Bill Woodward (Chairman, SAE International Aerospace Avionics Systems Division), I’ll present “NEW INTERFACE REQUIREMENTS: IMPLICATIONS for FUTURE“.  By “future” we indicate the initiation of a task to conclude with a SAE standard that will necessitate appearance of separate satellite measurements to be included...Read More
16 Jul, 2016
A recent video describes a pair of long-awaited developments that promise dramatic benefits in achievable navigation and tracking performance.  Marked improvements will occur, not only in accuracy and availability; over four decades this topic has arisen in connection with myriad operations, many documented in material cited from other blogs here. 
12 Feb, 2016
For reasons, consider a line from a song in Gilbert-&-Sullivan’s Gondoliers: “When everybody is somebody, then nobody is anybody” — (too many cooks) For consequences, consider this question: Should an intolerable reality remain indefinitely intolerable? While much of the advocacy expressed in my publications and website have focused on tracking and navigation, this tract concentrates...Read More
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