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Comment Re:Fracking to relieve tectonic pressure (Score 1) 265 265

The subduction zone may be located out to sea, but the subducted plate extends under the continental crust for a fairly long distance, and at even greater depths. The eastern boundary of the subducted plate can only be "mapped" by comparing hundreds of seismic images and estimating density, temperature, and composition to determine what is still there to fracture and what has been sufficiently reabsorbed into the mantle.

Note that the current subduction system with a transverse zone to the south has been in place since the Pacific Plate made contact with the American Plate around 30 million years ago, dividing (and fracturing) the old Farallon Plate (of which Juan de Fuca is one remnant).

And as for potential worse-case scenarios, look at the Chilean subduction zone, and the 1960 Valdivia earthquake . The subducted Nazca Plate there is the southern remnant of the old Farallon Plate.

Comment Another reason to kill PowerPoint (Score 2) 327 327

I work in the education industry in a large-format print environment. PowerPoint is one of the main pieces of software chosen to make large academic posters (36" x 48" commonly, but I've had larger than 60"x 96" designed in PowerPoint). It is also the main reason there are delays and errors with said posters.

Our department strongly recommends that faculty and students use either Adobe Illustrator or the free open source Inkscape to create their posters. Less than 1% of posters created in these programs have any issues with the format, while PowerPoint currently has issues in roughly 50% of the files we have received in the past, with PowerPoint in an OSX system being by far the worse offender. The problem has been somewhat mitigated with requiring all submissions be in PDF (which works well with our proprietary ripping software), but has only reduced the issues, not eliminated them.

It should be noted that various other office suites and other programs have been used to generate the posters we print, but nothing is quite as bad as those coming from the Microsoft Office suite (don't get me started on Publisher). And to those suggesting a raster export (jpg, tif, png, bmp, etc) the files quickly become to large for an average user to move them easily (less an issue today than 5-10 years ago) and text/finer elements often become fuzzy and plugged in all but the highest resolution files.

So yes, please, let's all kill PowerPoint (and throw Publisher on the pyre while we're at it).

Comment San Bernardino County Resident (Score 2) 104 104

"Alternatively, it might suggest that the government just doesn't care about legal authorization."

As a resident of San Bernardino county (for 15+ years) who has personally known many members of the Sheriff's Department, I'd suggest that this is indeed the case. This county is the largest in the nation and has population widely dispersed throughout a vast majority of it's area, making deployment difficult. The attitude I saw most prevalent was one of "I don't care, just get it done". A perceived relative lack of equipment and manpower coupled with this attitude means that corners get cut and protocols are ignored.

They do, however, and more often then not, get the job done.

Comment Re:ST only needed transparent aluminum for... (Score 1) 247 247

Plot wise, transparency wasn't the issue (although it was a selling point to get the stuff made), it was to reduce the material thickness required to hold the water from 6" thick to 1" thick, and to barter the knowledge of it's creation for the requisite material.

Here's the clip: https://www.youtube.com/watch?...

Comment Re:Pffff... Magnitude 7? (Score 2) 63 63

Try living in the area and building in the area before you start speaking of things you seem to know nothing about.

Well, my home is within 10 miles of the San Andreas Fault, and my work is built entirely within the historical San Andreas fault zone (my office lies less than 1/2 mile from the current southern branch). I am a native Californian and have ridden out many earthquakes, both in and out of school.

And to address other concerns, the Field Act is insufficient for the high end for potential quakes. It it designed to handle M7 quakes, while historical data shows that a M7.9 has occurred in California. Note that the strongest quakes since 1933 were 2 M7.3. My research in getting my BA in geology showed that up to about a M9 could theoretically be possible, and that the historical data may be underestimated (the 1812 Wrightwood-area earthquake had one report suggesting a possible M9.2).

Also, I was generally estimating the design, but I was also referring to low one story buildings, as opposed to multiple floor structures. Larger buildings require a very different approach to their foundations (in order to reduce oscillation). The original statement said "withstand a 8.0 without structural damage" and while a M8.0 off a subduction zone is no where near as powerful as a M8.0 off a transverse zone at the surface, I seriously doubt that any country has the economics to build to such a high standard across the board.

Comment Re:Pffff... Magnitude 7? (Score 5, Informative) 63 63

Laws requiring all structures to withstand an 8.0? Let's move past the enforcement nightmare that would be and look at the reality of building that strong, It would cost close to million US dollars to build a single floor, single family dwelling to those specifications. You would need a foundation between 36"-48", fully steel enforced, likely 6"x12" studs throughout 16" on center and 12'x12' or larger corner posts. The roof structure would weigh 5 to 7 times what a normal roof would, and every single wood joint would have to be reinforced with 1" thick steel plate, bolted through the stud and beam centers.

In California structural laws are designed to preserve human life, and structures are designed to survive the shaking enough to allow people to exit, but we take the Japanese mentality that natural disasters will do damage, and it's better to rebuild every few decades.

Besides, California is a transverse zone (primarily, north of Mendocino is subduction with divergent off shore, and some divergence from the Salton Sea south) and we deal with shallow M7-M9 earthquakes, while Chile runs along a subduction zone, with deep M15+ quakes. Your quakes have much more energy dispersed over a larger area, while ours tend to be more localized and focused. We get at most 3-5 minutes of shaking, with less than a minute of intense damaging waves, while you can have 5min+ of building-toppling destruction,

Comment Re:Still objects more dangerous than moving object (Score 2) 85 85

Do we not have to worry the most when the faint objects do *not* move at all, between pictures? Then they are heading straight for us.

Incorrect, we are judging their movement as compared to the background stars, which are (relatively) fixed in position while we move. An object on collision course with us will not be heading straight the position we are at when it is observed, but it's trajectory will have to carry it into the path of our orbit, at the same time that we occupy that same point. If an object appears in the same fixed position as the starts around it, it is either too distant to concern us, or it is in a concentric orbit at the same angular velocity as us and not an issue (although this would be an extremely interesting discovery).

Even something on a perfect spiral trajectory on the elliptical and matching our angular velocity would be detectable due to observations at different times of the night (as we rotate around the Earth's axis) and the different Doppler shift compared to much more distant stars.

Comment Re:Realistic (Score 1) 374 374

Another possibility might be working on lower loss, high capacity transmission lines (or methods), and bridge the various grids to move solar generated power to the darkened parts of the country and possibly planet. A global electrical network with multiple redundancies could help stall many power crises and reduce loss from current storage methods.

Comment Re:The elephant in the room (Score 1) 698 698

I disagree, perhaps letting them know that it's okay for them to move on with their lives, even if it means not watching later videos/opening future letters. My wife has made it clear that if she passes early she wants me to remarry, for our children. If I were in your situation I would remind them in each message not to dwell on the past, but to feel free to move forward. Tell them that you have made these messages not as a way to tie them to you, but to stand behind them during the important and often difficult times.

Comment Don't forget your wife (Score 2) 698 698

As (I hope) others may have said, make sure you also make some videos for your wife. Help her to be the best Mom she can be. Help her to know what qualities you loved about her. Help build her up, so that she can be there for your daughter when you cannot. Birthdays and anniversaries will likely be the hardest, planned some timed messages for then. I don't know about your religious views, but I believe strongly that the bonds of marriage can last beyond death.

When you have to leave a job or project that you love, you give your all to make sure that it will continue well after you leave. A family is the greatest project any of us will be a part of, and with you passing away your wife will be the sole top administrator. Give her tools for that bad times, when she'll not feel up to the task. Encourage her, let her know that she is wonderful and completely capable. Let her know your approval, gratitude, and love for her.

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