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Comment Re:Wait... (Score 1) 911

90% carbon dioxide? 8 percent is lethal, and I haven't heard of anyone dieing from breathing someone else's breath. Breath is actually about 4% carbon dioxide.

The bigger deal with breathalyzers is that they make an assumption about the rate at which ethanol diffuses from the blood into the lungs, which I've forgotten the units for, but could easily vary from 1200-4200, with some outliers of 900 and 5000.

Comment Re:Isn't space 'cold'? (Score 1) 153

Space doesn't really have a temperature. Temperature and conduction of heat requires particles to bump into each other. You feel something being hot because the molecules in it are moving very quickly. You feel something being cold because the molecules in it are moving slower. However in space there are (almost) no molecules.

Thus the only ways to lose and gain temperature are via radiation (not necessarily ionizing radiation), and internal heat generation. The sun is radiating energy onto the satellite and the satellite is radiating energy. However as the satellite isn't very hot, it doesn't radiate a whole lot, thus is tends to heat up.

All of the electronics on the satellite are producing heat as they work, and I suspect that this is where most of the heat of the satellite is coming from.

This isn't all that important for most satellites as they can work at higher temperatures, however the sensors on the WISE needs to be kept cold. Since the sensors on the WISE work in the infrared part of the electromagnetic spectrum, and all things radiate infrared (unless they're at absolute zero) if the sensors are too hot, they will just detect their own infrared radiation rather than the radiation from the objects in space.

Comment Re:Makes sense (Score 1) 1123

The "law" of gravity is really just a theory with a lot of support (experiments) to back it up.

I don't disagree with most of your post, except for two points. One is that there is a law of gravity and a theory of gravity. The law states what the force of gravity is, and the theory states why there is gravity. The second is that the main problem with putting science and religion in the same room is when people try to use their religion to influence the conclusions of science, or more generally when people use their religion to attempt to influence others in an area other than strictly religion.

I think the reason some people try to use science to disprove religions is that other people try to use religion to disprove science.

At the end of the day beliefs should not be used to dictate reality.

Comment Re:Temporary tags maybe? (Score 4, Insightful) 108

RFID and earthquakes

One major thing everyone overlooks is the range of RFID. To be small enough to comfortably fit in a human only a passive unit with a small antenna can be used. This limits the range since the power has to be pushed to the RFID tag. You're going to get a range of maybe a meter.

Additionally no materials that respond to a magnetic field can be used, as it would tear out the tag during an MRI. From a security standpoint, want to become someone else? take their chip. After all, it's a perfect ID system, so if it says you're joe, there's no way you could be bob with joe's chip. (This is why there are photos on id, although it's much more difficult to steal a chip than a card)

I've also never figured out how they can listen to multiple tags at once, the same type of tag is going to be on the same frequency, so don't their transmissions overlap?

Finally there is no time when an earthquake is supposed to happen, except for aftershocks (in which case if the original earthquake is strong enough to warrant getting your tag, it's probably too late anyways)

Comment Re:How About Just ID'ing "Not the Patient" DNA? (Score 1) 103

That would result in too many false positives.

It wouldn't be too difficult (relative to this) to make something that reacted to any DNA that's not eukaryotic. But chances are, that there are a bunch of different little bacteria going through your blood. These bacteria just haven't been caught by your immune system yet, but aren't really doing any harm. There's no guarantee that these pathogens even harm humans, just that they've somehow ended up in your blood.

Comment Why?! (Score 1) 352

Why do they even need people to look at these at all? The human form is rather smooth, and it should be simple enough to write an algorithm that detects anomalies and gives a human a picture of just that area. Or not even a picture, just tell the screener what area needs to be searched. If we are to believe that these scanners go all the way down to the person's flesh, then it would be nearly impossible to make any kind of weapon smooth enough to be undetected by an algorithm.

Additionally I hope that these scans aren't being stored. At most they should be allowed to be stored for a day, after that the person's been arrested and you can pull the scan from the system for evidence, or the person has already gotten onto the plane, flown, and landed on the other side.

Comment Re:What can be done? Nothing. (Score 1) 511

One of the basic concepts in physical security is having the 'key' be in two parts, something you have and something you know. The idea of the debit/credit card is that it needs to be physically present in order to make the transaction, but that has gone away with online purchases.

There are two major fixes that could solve a lot of these debit / credit problems. One is to have the number on the card be different than what is stored on the magnetic strip. This way, when the thief gets a hold of the data on the strip, they have to make a new card and can't make online purchases. It's not difficult to make a new card with the data off the strip, but it just makes it that much more difficult, especially when the thief goes to use it and the merchant refuses because it's a generic card and not one from a bank.

The other major fix is to put a time changing number into the card. I can't think of the right word, but it would be a digital display with a number that changes every so often, anywhere from 5 minutes to a day would easily work. The bank knows what that number should be at any point in time and that particular card knows, so now you really do need the card in order to use it online.

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