Re: Financial topics
Posted: Mon May 25, 2015 3:05 pm
Juggalows over thar also http://www.rferl.org/content/ukraine-le ... 90324.html
Waka Flaka Flame in July
Waka Flaka Flame in July
Generational theory, international history and current events
https://www.gdxforum.com/forum/
Structures made out of metals and other materials have defined failure points. A material fails when subjected to a stress equal to its tensile strength (or tensile strength adjusted by the geometry of the structure). A material also fails with regularity after a defined number of stress cycles. These failure points can be demonstrated repeatedly and the test methods defined so that it can be predicted where the material will fail with a high degree of certainty. A software system doesn't have a defined failure point or any material properties that can be demonstrated.John wrote:I'm not so sure about this, Higgie.Higgenbotham wrote: > A structural engineer should be able to tell approximately when a
> bridge will fail based on design principles and looking at the
> structure.
Recall the paper that I referenced a few weeks ago:
** How Complex Systems Fail, Richard I. Cook, MD
** Cognitive technologies Laboratory, University of Chicago
** http://GenerationalDynamics.com/gdgraph ... msFail.pdf
Note the following paragraph:
Applying this to the bridge situation, a structural engineer might> 3) Catastrophe requires multiple failures – single point failures
> are not enough. The array of defenses works. System operations
> are generally successful. Overt catastrophic failure occurs when
> small, apparently innocuous failures join to create opportunity
> for a systemic accident. Each of these small failures is necessary
> to cause catastrophe but only the combination is sufficient to
> permit failure. Put another way, there are many more failure
> opportunities than overt system accidents. Most initial failure
> trajectories are blocked by designed system safety
> components. Trajectories that reach the operational level are
> mostly blocked, usually by practitioners.
evaluate a bridge and decide that there are no significant risks of
catastrophe. But he cannot predict when a "perfect storm" of minor
failures combine in an unexpected way to produce a major catastrophic
failure. I know that's what happens in large software systems.
After I posted this, I recalled the fundamental reason why this is true. It's because metals are arranged atomically into lattice structures that are uniform. The lattice structures have uniform distances between the atoms, uniform forces of attraction, etc., that don't vary.Higgenbotham wrote: Structures made out of metals and other materials have defined failure points. A material fails when subjected to a stress equal to its tensile strength (or tensile strength adjusted by the geometry of the structure).
In an old bridge this is not so easy because you need to know how much metal is left in each of the parts. Once there is rust you need to know how much rust. It costs to do the inspections and it seems they are often not done.Higgenbotham wrote:After I posted this, I recalled the fundamental reason why this is true. It's because metals are arranged atomically into lattice structures that are uniform. The lattice structures have uniform distances between the atoms, uniform forces of attraction, etc., that don't vary.Higgenbotham wrote: Structures made out of metals and other materials have defined failure points. A material fails when subjected to a stress equal to its tensile strength (or tensile strength adjusted by the geometry of the structure).
from the above link --vincecate wrote:In an old bridge this is not so easy because you need to know how much metal is left in each of the parts. Once there is rust you need to know how much rust. It costs to do the inspections and it seems they are often not done.Higgenbotham wrote:After I posted this, I recalled the fundamental reason why this is true. It's because metals are arranged atomically into lattice structures that are uniform. The lattice structures have uniform distances between the atoms, uniform forces of attraction, etc., that don't vary.Higgenbotham wrote: Structures made out of metals and other materials have defined failure points. A material fails when subjected to a stress equal to its tensile strength (or tensile strength adjusted by the geometry of the structure).
http://www.nbcnews.com/id/20998261/ns/u ... WWLb9RdXC8
I find that the media often dwells on whether inspections got done without ever commenting on whether the inspection were done correctly. They talk as if doing an inspection is a cure-all. I can attest to the fact that in my experience the act of inspecting something is not always meaningful.vincecate wrote:In an old bridge this is not so easy because you need to know how much metal is left in each of the parts. Once there is rust you need to know how much rust. It costs to do the inspections and it seems they are often not done.Higgenbotham wrote:After I posted this, I recalled the fundamental reason why this is true. It's because metals are arranged atomically into lattice structures that are uniform. The lattice structures have uniform distances between the atoms, uniform forces of attraction, etc., that don't vary.Higgenbotham wrote: Structures made out of metals and other materials have defined failure points. A material fails when subjected to a stress equal to its tensile strength (or tensile strength adjusted by the geometry of the structure).
http://www.nbcnews.com/id/20998261/ns/u ... WWLb9RdXC8
As in this article, I find that the media often dwells on whether inspections got done without ever commenting on whether the inspections were done correctly. They talk as if doing an inspection is a cure-all. I can attest to the fact that in my experience the act of inspecting something is not always meaningful.vincecate wrote:In an old bridge this is not so easy because you need to know how much metal is left in each of the parts. Once there is rust you need to know how much rust. It costs to do the inspections and it seems they are often not done.Higgenbotham wrote:After I posted this, I recalled the fundamental reason why this is true. It's because metals are arranged atomically into lattice structures that are uniform. The lattice structures have uniform distances between the atoms, uniform forces of attraction, etc., that don't vary.Higgenbotham wrote: Structures made out of metals and other materials have defined failure points. A material fails when subjected to a stress equal to its tensile strength (or tensile strength adjusted by the geometry of the structure).
http://www.nbcnews.com/id/20998261/ns/u ... WWLb9RdXC8
Detection of reinforcing bars in concrete is one of the most widespread applications of GPR in
Civil Engineering [20, 22, 23], but the results is very difficult to interpret and may require the skills of
an experienced operator and the use of lengthy manual post-processing and subjective expertise to
produce a reliable end result [10, 15].
The fitting technique is applied on a variety of real hyperbolic signatures that are collected from
a controlled test site, the results indicate this technique is fully capable of successfully estimating
the depth and radius to within 10%, which validates the method and justify the assumptions used.