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Comment Foundation Repair (injection) (Score 5, Interesting) 94

It seems to me that this type of technology could be used on pre-existing concrete as well. Assuming it is strong enough, and it seems to be, it could be injected into foundation cracks. The crack would be fixed from the inside out. The savings in time and money would be enormous and it would be vastly superior to current methods of foundation repair.

Submission + - Quantum Computing (

slackoon writes: From the Article: "Quantum mechanics is now being used to construct a new generation of computers that can solve the most complex scientific problems—and unlock every digital vault in the world. These will perform in seconds computations that would have taken conventional computers millions of years. They will enable better weather forecasting, financial analysis, logistical planning, search for Earth-like planets, and drug discovery. And they will compromise every bank record, private communication, and password on every computer in the world — because modern cryptography is based on encoding data in large combinations of numbers, and quantum computers can guess these numbers almost instantaneously."

"Imagine being able to open a combination lock by trying every possible number and sequence at the same time. Though the analogy isn’t perfect — because of the complexities in measuring the results of a quantum calculation — it gives you an idea of what is possible."

Should we be worried or excited?

Comment Re:gosh (Score 1) 164

>The reality is that we're not just trying to keep nukes out of the hands of the Iranians, we're trying to make sure that the rest of the ME doesn't enter an arms race which puts nukes in the hands of other countries.

>And who exactly appointed you to do that ?

Being a moral and just society who thinks of others is what appointed The U.S.A. and it's allies to "do that". Countries like Iraq, Libya and others have proven they cannot even keep their own people safe. They have little to no ability whatsoever to safely keep stockpiles of munitions. So why would we want them to have NUKES? organizations like ISIS would get them very quickly, then what? It sounds great to say but what about protecting the innocent who cannot protect themselves. If ISIS did use a nuke, who would be responsible for that? ISIS, the country they got it from, the country who could have stopped it? ALL OF THE ABOVE!

In World War II should we have just let them handle it themselves. Well that depends, are you OK with genocide, would you like saying hail Hitlerlet’s get real here!

Comment 200m? (Score 2) 106

I found more information here: more information There is mention of 200m: "We believe the aquifer beneath Lake Vida is a remnant of a time when the water levels across [the valley] were much higher than present. Upwards of 200 meters higher,”. However, the instruments they were using were only capable of penetrating 600M so it's definately not 200 miles!!

Comment Rail gun vs. "Conventional" (Score 2) 517

The bullet in this case is just a massive piece of metal. It is accelerated to a ridiculous speed (a Navy weapon capable of hurling 40-pound projectiles at speeds of 4,500 mph to 5,600 mph over 50 to 100 miles (7,240 to 9,010 kilometers per hour over 80 to 161 kilometers). This is the advantage of railguns, very high bullet speeds. This gives the bullet a massive amount of energy.

The weapon works by basically smashing into something else, transferring most of that kinetic energy into whatever it hits which ultimately ends up as heat. This is the same reason brake pads on cars get hot, transfer of kinetic energy into heat.

When the projectile hits something and stops, the bullet and whatever it hits will get very hot. The projectile is probably made of metal which is in fact very flammable if you get enough oxygen to it. So there is a fireball, either because whatever it hits is flammable or because the projectile/whatever it hits is burning.

When you hit something that fast the behavior of metals changes. The speed of sound (see * below) in metal is high but if you hit something fast enough, then you can actually exceed the speed of sound in a metal and the rear of the projectile will carry on moving as though it hasn't hit anything when the front has hit something. This is the same idea of a shock-wave in air but it's in metal. Heres a good youtube video:

Well needless to say this tends to result in some funky stuff, like the metal bullet tearing it's self apart into lots of small pieces. This is a big driver in some anti-tank weaponry. If you hit the armour just right then you can actually get the inside of the tank to shatter, basically turning the inside of the tank into a shrapnel grenade, killing the operators.

If the projectile shatters then it's going to be hot and have a large surface area and you can get lots of oxygen to it which will result in a fireball, potentially it will burn about as hot as 1000 K. This to me seems like a good thing to design for because the added heat is going to do things like start fires and ignite conventional bullets/warheads and burn through armour.

* The speed of sound refers to the maximum speed at which a mechanical vibration (much like the pressure changes that cause sound. Not like light, RF, or electricity) can travel through a medium. Mach1 refers to that maximum speed of those wave's permeation through air, however different media such as water, metal, and glass will have different values for that maximum speed.
So, as the projectile hits some theoretical immovable object, the front will stop, but the rest will continue collapsing in on the front, faster than the pulse created on initial impact (a mechanical vibration that would otherwise influence the rear of the projectile to slow down) can travel to the rear of the projectile.
A bad, but visual representation of this is if you had a long line off cars driving down the freeway bumper to bumper. The first crashed and was brought to a halt instantaneously. In a normal crash each car behind would generally apply brakes and slow down before impact. However, for this example, everyone is driving faster than their own reaction time, so they are part of the pileup before they have registered an accident happened in the first place.

Comment won't automatically connect to WiFi (Score 1) 120

I have to say that my internet on my MacBook pro still drops once in a while. However it's drastically improved. The biggest thing is that I would have to select the network and re logon every time I woke up the computer. it never did it automatically. Now it does!!

As discussed on this forum

1st World Problems ;)

Comment introduced species...OH NO!!! (Score 1) 265

The Cane Toad was also a "good idea" with a "proven background" and...well...we all know how that went

"The cane toad is native to South and Central America, but when its introduction to regions of Hawaii, the Caribbean, and the Philippines to fight pests in sugarcane fields yielded impressive results, it was quickly imported to various other regions worldwide.

Unfortunately, cane toads have a nasty habit of not just eating crop pests and insects, but also just about any terrestrial animal that they can fit their grotesquely huge mouths around — which is saying something, given that they can grow to over 30 cm in length. They also secrete toxins capable of killing just about any animal they come in contact with (humans have died after ingesting their eggs), meaning that they tend to be seriously lacking in the natural predator department."
Source here

Comment what the vaccine actually do? (Score 2) 178

from the article "Though a vaccine wouldn’t be a silver bullet—there would still be withdrawal symptoms—a person may be less motivated to relapse because the brain’s reward system could no longer react to nicotine"

so for all those being critical of this vaccine please keep in mind it's not supposed to "make you quit". It's more like it takes away your reason for doing it. Smokers will no longer get the good feelings from a cigarette so they will be more inclined to quit. If used as a vaccine they will be less likely to start again or start in the first place.

Submission + - Anonymous claim first victory against jihadists

slackoon writes: 'Hacktivist' group Anonymous has fired the opening salvo in its online war on terror groups following the Charlie Hebdo massacre.

The loose-knit collection of hackers said it would shut down jihadist websites in retaliation for the terror attacks on the Paris-based office of the French satirical newspaper and a subsequent attack on a Jewish deli on Friday.

Now it has emerged that the group, which holds freedom of speech sacred, claimed on Twitter that it had struck, a French terror-mongering website.

The Twitter account, @OpCharlieHebdo, also posted '#TangoDown', a reference to a military term meaning a terrorist has been eliminated. Source

Submission + - Thermocouple technology

slackoon writes: The lantern’s operation is based on a phenomenon known as the Seebeck effect, using thermocouple technology to generate an electrical current by exploiting the temperature difference between the inside of the lantern and the cooler outside air. As long as the candle inside the lamp housing is burning, the LEDs will continue to emit light.


This thing actually works, question is, how can we use this tech in a proper /. kinda way?

Comment Re:Study debunks nothing at all, move along (Score 1) 19

I could not agree more. It's the widespread layering of strata that leads researchers to believe there was an impact. As you said "Those scoria were indeed local and made in fires - like the vast fires that spread everywhere after the airburst" So unless there were BILLIONS of fires lit over an ENORMOUS area then it wasn't "Stone age house fires".

In addition I'd like to point out that there are countless studies that support the conclusion that a cosmic impact triggered the Younger Dryas cold period and only a handful that support otherwise.

Comment What result are they looking for? (Score 1) 448

So there should be a fundemental research question that this research will answer, what exactly is that question?
"What’s most exciting about this channel of research is that it gets at the kind of complex, subtle prejudices that most people can’t even articulate if asked directly."
in other words...

They are going to try to find racism where none actually exists and then call white people racist.

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The bogosity meter just pegged.