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Comment: Re:"because it originated from the wireless networ (Score 1) 547

by Cedric Tsui (#45729327) Attached to: Harvard Bomb Hoax Perpetrator Caught Despite Tor Use
It'll stand. This is in the Affidavit.

9. Harvard University was able to determine that, in the several hours leading up to the receipt of the e-mail messages described above, ELDO KIM accessed TOR using Harvard’s wireless network.
10. On the evening of December 16, 2013, an FBI agent and an officer of the Harvard University Police Department interviewed ELDO KIM at the building in which he resides on the Harvard University campus. During the interview, the FBI agent advised KIM of his rights under Miranda. KIM read and signed an advice of rights waiver, stating that he understood his rights. KIM then stated that he authored the bomb threat e-mails described above. KIM stated that he acted alone. He further stated that he sent the e-mails to “five or six Harvard University e-mail addresses” that he picked at random from the university’s web page. According to KIM, he was motivated by a desire to avoid a final exam scheduled to be held on December 16, 2013.

Comment: Re:Have they studied physics? (Score 1) 438

by Cedric Tsui (#44418893) Attached to: "Slingatron" To Hurl Payloads Into Orbit
Points 1 and 2 are accurate though. From TFA:

"...the G-forces involved are tremendous with the projectile subjected to up to 60,000 times the force of gravity.
It’s questionable whether any rocket system could survive such stresses..."

Disagree! It's not questionable!!! Have you even seen a rocket? Do you have ANY idea how finicky those things are? Have you considered that the ROCKET FUEL inside the ROCKET might be a weeeeee bit unstable?

Comment: Re:Throwing the NOT flag here.... (Score 1) 181

by Cedric Tsui (#44311619) Attached to: New Thermocell Could Turn 'Waste Heat' Into Electricity
Agreed. This does not help at power plants.

But, forget about the efficiency game for a second. We're talking about waste heat. For instance, the catalytic converter under my car gets wicked hot, and that heat just gets swept away by the draft. This thermal gradient is free. So long as the device itself is cost effective, I think we have a winning combination. It's infinitely more "efficient" than an alternator which draws useful energy away from the engine.

But. In the big scheme of things, removing the alternator isn't going to make a drastic improvement in gas mileage. The biggest advantage I see is that the thermocell has no moving parts (I think...) and should be quite a bit cheaper to manufacture than an alternator.

Comment: Re:I'd take that with a truckload of salt (Score 1) 201

by Cedric Tsui (#40095239) Attached to: Little Health Risk Seen From Fukushima's Radioactivity
Everything I've read here has been consistent with previous statements. What is it exactly that you feel they could be lying about?

The problem they're addressing with this article is that two control room workers didn't take their potassium iodate tablets, which means they received a much higher dose than they otherwise would have. Their dose is high enough that there's a chance that they would experience the effects of radiation poisoning. But they didn't.
Aside from that, their lifetime chance of developing cancer increases from 40% to 45% (back of envelope calculation. Could be wrong. Assuming 8% increase risk per Sv). That's not something you can notice... If the other workers, or the general public have an increased risk of developing cancer, those risks are also too small for anyone to notice. I think that's all they're saying.

Comment: Re:Ah, nice BULLSHITTING (Score 1) 233

by Cedric Tsui (#34437394) Attached to: A Third of World's Spam From One Russian Man
Wait. Hold on a second.
The police are not allowed to shoot a criminal because he is resisting arrest or fleeing a scene. They are only allowed to shoot someone if they are posing a threat to someone.

At least, that's how I presume gun use by police works. That's how it work in Canada. In fact, since there was a polish man who died after being shot with a taser, the same rules now apply to them.

Comment: Re:Might save your gonads from radiation too (Score 1) 325

by Cedric Tsui (#34320608) Attached to: Underwear Invention Protects Privacy At Airport
nonsense! You're just pulling numbers out of your hat to scare people.

The dose from one trip through the xray backscatter scanner is 0.05 Sv, which is completely negligible compared to any other x-ray diagnostic.
Wikipedia compares this dose to the radiation from being in an airplane (higher in the atmosphere) for 6 hours is 20 Sv. 200-400 times greater.

Comment: Re:Any time soon? (Score 1) 152

by Cedric Tsui (#34238320) Attached to: Aerial Drone To Hunt For Life On Mars
I think this is basically just an aerodynamic satellite with a few wings. They'll put it in a low orbit at a high inclination, and it'll do circles until the orbit starts decaying. It wont use it's jet engines and manoeuvrability until the end of its mission, hopefully to check out a list of extra interesting targets.

Comment: Re:Kind of makes you wonder... (Score 4, Insightful) 343

by Cedric Tsui (#32894952) Attached to: Infants Ingest 77 Times the Safe Level of Dioxin
I don't think so.
This is a common problem in terms of safety standards. Toxicity of a substance is very hard to quantify. It's easy to take a group of lab rats and see what dosage kills half of them. But what does that say about how tiny amounts of the substance will affect your lifetime chance of developing cancer? Usually, you cant say anything!

If it can't be quantified, then you assume the worst case scenario. I know that when it comes to radiation, we call this the 'linear, no threshold' (LNT) model. If x amount will bring you 50% of the way to death, then x/500 will bring you 0.1% of the way to death. There is no safety threshold, which means that we assume that any ingested amount no matter how small does damage.

Now, the LNT model is pretty much never correct. At least, I've never seen an example where it has held. One example: Swallowing two pounds of vitamin C should kill me based on the LD50 for rats. If we were to apply the LNT model, we'd conclude that vitamin C is toxic and I shouldn't ingest any if I can help it. It's this kind of reasoning why lexan bottles are no longer covering the shelves. Some scientist measured 6-20 parts per billion of BPA in the water contained in one of these bottles.

Does that mean the EPA is unreasonably over protective? Yes. Do I want them to change? ABSOLUTELY NOT! In this case, as in the case for radiation, and for BPA, pseudo estrogen, mercury, etc.., is that we can not prove that exposure to these quantities is safe, and we have reason to believe that they are not. They do not need to be proven dangerous to be banned. They need to be proven safe to NOT be banned.

Comment: Re:Too Controversial (Score 1) 875

by Cedric Tsui (#32286560) Attached to: National Academy of Science Urges Carbon Tax
I disagree.
When seat belts were first introduced, no one used them. Even with all the experts in complete agreement about the potential benefits one would gain by wearing a seat belt. But it was a big change, and it was a major pain. The government made an unpopular move to enforce seatbelt use, and started fining people who did not. The risk of losing your life wont make you wear one, but the risk of a fine will!

I think you give the government too little credit. If enough people agree that issuing carbon taxes is the right thing to do, even if it's not something we'll enjoy, then we'll get them. Then one day, we'll be so used to them, we'll have trouble remembering what all the fuss was about!

Comment: Re:Best prank ever (Score 1) 217

by Cedric Tsui (#31751086) Attached to: Jordanian Mayor Angry Over "Alien Invasion" Prank
No kidding. These kinds of pranks can be DANGEROUS.
On August 31st, 2005 in Baghdad, there was a large crowd of Shiites on a pilgrimage crossing a crowded bridge. Someone somewhere on the bridge said something about suicide bombers, and this sparked a horrible panic which turned into a stampede. Over 950 people died from being crushed, suffocated or drowning after jumping or falling into the Tigris. This probably wasn't a prank. It could have been malicious, or maybe there are words that rhyme with suicide bomber in Arabic. But it does demonstrate how dangerous a prank can be.

It is the quality rather than the quantity that matters. - Lucius Annaeus Seneca (4 B.C. - A.D. 65)