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Harvard Bomb Hoax Perpetrator Caught Despite Tor Use

Cedric Tsui Re:"because it originated from the wireless networ (547 comments)

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.

about 9 months ago

Canadian Hotel Sues Guest For $95K Over Bad Review, Bed Bugs

Cedric Tsui Re:Other posts? (432 comments)

The hotel can sue this individual for slander. The only way you have a case for slander is is you can prove that the accusations are unfounded. That's not easy. The only reason they would be suing is because they think they can win. Well... either that or they're stupid.

1 year,28 days

Hybrid Hard Drives Just Need 8GB of NAND

Cedric Tsui Re:Just buy more RAM (373 comments)

Sounds about right. You would only lose the boot time improvement by getting ram instead of NAND memory. I think you're wrong about the pricing though. The NAND memory of an SSD drive is cheaper than RAM. Otherwise, these drives wouldn't exist in the first place.

about a year ago

"Slingatron" To Hurl Payloads Into Orbit

Cedric Tsui Re:Have they studied physics? (438 comments)

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?

about a year ago

"Slingatron" To Hurl Payloads Into Orbit

Cedric Tsui Re:I see an obvious problem with this concept: hea (438 comments)

The article says that a heat shield is necessary. You can dump the heat-shield once you leave the atmosphere and before you perform your burn.
The concept is silly, but not for this reason.

about a year ago

New Thermocell Could Turn 'Waste Heat' Into Electricity

Cedric Tsui Re:Throwing the NOT flag here.... (181 comments)

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.

about a year ago

Little Health Risk Seen From Fukushima's Radioactivity

Cedric Tsui Re:I'd take that with a truckload of salt (201 comments)

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.

more than 2 years ago

A Third of World's Spam From One Russian Man

Cedric Tsui Re:Ah, nice BULLSHITTING (233 comments)

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.

more than 3 years ago

Underwear Invention Protects Privacy At Airport

Cedric Tsui Re:Might save your gonads from radiation too (325 comments)

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.

more than 3 years ago

Aerial Drone To Hunt For Life On Mars

Cedric Tsui Re:Any time soon? (152 comments)

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.

more than 3 years ago

Infants Ingest 77 Times the Safe Level of Dioxin

Cedric Tsui Re:Kind of makes you wonder... (343 comments)

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.

more than 4 years ago

National Academy of Science Urges Carbon Tax

Cedric Tsui Re:Too Controversial (875 comments)

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!

more than 4 years ago

Facebook Crawler Speaks Back

Cedric Tsui Re:There's something I don't understand (317 comments)

The article says he looked for legal council, and this dispute falls into an untested portion of the law. It isn't clear of it is defensible.

more than 4 years ago

Jordanian Mayor Angry Over "Alien Invasion" Prank

Cedric Tsui Re:Best prank ever (217 comments)

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.

more than 4 years ago

90% of the Universe Found Hiding In Plain View

Cedric Tsui Re:Implications for dark matter estimates? (279 comments)

Dark matter is a VERY successful theory. It's not very popular among non-astronomers because it's difficult to wrap your head around, and it sounds hand wavy. But among the scientific community, the concept of dark matter isn't really debated. There are other theories, but none of them work.

The strange observation that sparked the dark matter idea was that stars at the outer edges of galaxies were orbiting much faster than one would predict. Either the laws of motion were incorrect (and VERY incorrect) or there was a large disk of unseen matter enveloping the galaxies. The former theory got pretty much tossed out because the deviation from theory was different from one galaxy to another. So either there are different amounts of dark matter around various galaxies, or the laws of physics are different in different places.

Today, it is possible to observe gravational lensing. Light is bent by the curvature of space time, and we can see that because the 'lenses' will curve the light from a distant star into a ring or an arc. The take home message is that space-time is curved out there in a way that can not be caused by visible matter. It's possible that space is just bent and there isn't anything causing it, or maybe there is a bunch of matter out there that doesn't interact in a way that we can observe it. Either way, we'll call it dark matter until we learn enough about it to give it a better name.

more than 4 years ago

90% of the Universe Found Hiding In Plain View

Cedric Tsui Re:Next step: a better name (279 comments)

They've come up with better names.
There was a group working on the OWL. The OverWhelmingly Large telescope. But the funding got slashed, so all we're going to get is the Extremely Large Telescope.

more than 4 years ago

How Earth Avoided a Fiery Premature Death

Cedric Tsui Re:The article isn't great for the lay-person (114 comments)

"Nope, they have to have ENOUGH velocity"
Yes. That's why I said things in orbit (meaning they already have an appropriate amount of speed in the right vector) stay in orbit... I didn't say random objects in the solar system stay in orbit.

more than 4 years ago

How Earth Avoided a Fiery Premature Death

Cedric Tsui Re:The article isn't great for the lay-person (114 comments)

"Throw a ball up... it comes down. This is gravity. The "base state" for gravity is everything sticking in the centre."

Nope. Your ball analogy doesn't work here. Things in orbit STAY in orbit unless they somehow lose all of their kinetic energy. A ball behaves differently because it NEVER gains enough energy for an orbit. The article says it is the interaction between the cloud and the proto-planet that causes the proto-planets to migrate towards the sun.

"We show that the planetoids from which the Earth formed can survive their immersion in the gas disk without falling into the Sun."

I can understand this part. But the article also says that a gas disk with varying temperatures would cause certain orbits to migrate outwards instead of inwards and THIS is why proto-planets can survive. But it doesn't say how a temperature gradient can cause migration.

more than 4 years ago

How Earth Avoided a Fiery Premature Death

Cedric Tsui The article isn't great for the lay-person (114 comments)

If I'm reading the article right, it says that the gravity of a gas/rock disk around a star will cause the whole thing to migrate inward until it is consumed by the sun. However, account for temperature differences due to varying cooling rates across the disk, then this causes a different force which can be shown to balance out the inward migration.

My question is. Why does the gravitational effects of a gas disk around a star cause inward migration? The only thing I would expect to cause inward migration would be friction resulting in the loss of kinetic energy. I haven't the foggiest idea how a temperature gradient can cause matter to climb out of a gravity well. Maybe I should go looking for the original paper.

more than 4 years ago


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