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Stories from March 12, 2011
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1.Dubai on Empty (vanityfair.com)
243 points by cwan on March 12, 2011 | 99 comments
2.Introducing NowJS or "How to make a chat server in 12 lines of code" (nowjs.com)
241 points by sthatipamala on March 12, 2011 | 32 comments
3.Why Gas Is So Expensive Today (Hint: It’s Not Libya) (cpeterson.org)
192 points by Apocryphon on March 12, 2011 | 106 comments
4.Video of reactor 1 at Fukushima plant (youtube.com)
176 points by taraharris on March 12, 2011 | 101 comments

Well, guess what, there's a lot of shit in this world. Go tell people to stop talking bad about Husni Mubarak, because after all, he's much better than Gaddafi and Saddam.

The fact is, people think Dubai is awesome. It's good journalism to uncover the truth about this supposed awesomeness.

Your only problem is that there are other places that are worse. As if suddenly everybody stopped noticing all the other bad places just because there's an article about Dubai.

The fact is, rich gulf states treat foreigner workers like slaves.

An interesting thing to note is how their youth are practically bullies. The same kind of bullies that PG talked about in his "nerds" essay[0], and his analysis of why people become bullies applies quite well to Dubai's situation. They are spoiled kids, they have no responsibilities, their lives are pretty pointless.

(EDIT: Lest somebody thinks I'm being racist: I'm an Arab myself.)

[0] http://www.paulgraham.com/nerds.html

6.HBGary planned to "blow the balls off Nmap" (seclists.org)
168 points by desigooner on March 12, 2011 | 101 comments
7.Securing an Ubuntu Server (andrewault.net)
168 points by chaosmachine on March 12, 2011 | 52 comments
8.Dear Twitter (helloform.com)
155 points by ssclafani on March 12, 2011 | 38 comments
9.Google’s Quest to Build a Better Boss (nytimes.com)
129 points by px on March 12, 2011 | 39 comments
10.IPad 2 introduces new headphone jack (fury.com)
128 points by bensummers on March 12, 2011 | 17 comments
11.Entire Japan coast shifted 2.4 metres, earth axis moves ten inches (vancouversun.com)
125 points by kevruger on March 12, 2011 | 45 comments

Laos isn't making a serious bid to be an international power player. Dubai is. The standards are different. Deal with it.

If you're going to build a civilization that depends on 70% of your population being foreigners, many of them second or third generation residents who have never seen their putative homelands, and you're going to reserve the right to deport them at will or to jail them for farting, then this article makes a very cogent point:

Your checks sure as hell better clear.

Dubai is not going to be fine.

13.Making of Crash Bandicoot - GOOL (all-things-andy-gavin.com)
102 points by _19qg on March 12, 2011 | 10 comments

There's really not much information in this article, and consequently it reads a tad sensationalist to me. Let me try to break this situation down as I understand it.

IAANRO (I Am A Nuclear Reactor Operator. I work part-time at my college's research reactor[1])

Nuclear power reactors are of two main varieties: Pressurized Water Reactors, and Boiling Water Reactors[2]. The plant in question is a Boiling Water Reactor (BWR). BWRs work by using the core's thermal energy to boil the cooling water into steam, and then channelling the steam in order to turn a steam turbine. After it exits the turbine, the steam is cooled in a condenser, where it turns back to water, and then is sent back into the core. The condenser requires cool water to be actively pumped through it, to keep the pipes upon which the steam condenses from becoming too hot. The water/steam that runs through the core and the turbine is referred to as the "primary cooling system", and the water running through the condenser is the "secondary cooling system." The primary is assumed to be contaminated (that is, it is measurably radioactive), whereas the secondary system is not, since it is isolated from the primary.

As far as I can tell, the chain of events for this particular plant went something like this:

Shortly after the quake, the reactor successfully shut down in anticipation of the tsunami. This means that no more fission is occurring in the core. Since a core meltdown is a result of uncontrolled fission, this means that the reactor is now incapable of melting down. This will not be another Chernobyl. However, just because U-235 is no longer fissioning, doesn't mean that the core isn't producing heat. The fission fragments (those isotopes produced as a result of the U-235 fissioning) will continue to decay through alpha, beta, or gamma emission, until stable elements at the bottom of the decay chain are reached. The decay of these fission fragments and their decay products will cause the core to continue to produce heat for some time after shutdown.

Presumably due to the fact that every reactor near the east coast of Japan was being shutdown, offsite power for the secondary cooling system was unavailable, so the power plant had to rely on onsite backup power, but the onsite power only lasted for 8 hours. After that, the secondary cooling system failed, which is what triggered the declaration of the Nuclear Emergency, and evacuation of those living within 3Km of the plant.

Since the core is continuing to produce heat, and consequently steam, the steam pressure inside the primary system is rising above normal levels. They are hesitant to bleed off steam into the containment dome, since the dome was probably damaged in the quake, but obviously bleeding off some steam is better than having the primary system rupture. Thankfully, most of the really nasty decay products have a relatively short half-life. In particular, Nitrogen-16, which gives off pretty high energy betas when it decays, has a half-life of 7.2 seconds.

Therefore, releasing the steam is undesirable, but not catastrophic, and probably not even particularly hazardous. The radioactive materials in the cloud will be longer-lived decay products of hydrogen and oxygen in, and as far as I'm aware none of those are particularly active. The cloud will be dilute itself after release, which will lower the intensity of the radiation field significantly. Therefore, the total radioactivity release will be many orders of magnitude lower than that of Chernobyl or Three Mile Island. The media is playing this up to be bigger than it is, because nuclear power still carries a stigma.

[1]: Reed Research Reactor: http://reactor.reed.edu/

[2]: Wikipedia Article on Boiling Water Reactors: http://en.wikipedia.org/wiki/Boiling_water_reactor

15.Music As Data - Music programming with Clojure (emotionull.com)
91 points by ique on March 12, 2011 | 18 comments
16.The Walled Garden Has Won (techcrunch.com)
89 points by joshbert on March 12, 2011 | 41 comments
17.The secret law of page harmony (retinart.net)
88 points by hackermom on March 12, 2011 | 12 comments
18.IOS 4.3 Nitro JS engine disabled for full screen apps and uiwebview (mobilexweb.com)
88 points by marcusramberg on March 12, 2011 | 43 comments

Like they wouldn't have boron near a nuclear reactor. I'm a PWR man myself, but I am 99% sure that GE BWR designs have a couple of big tanks of borated water specifically for a LOCA. I highly doubt they're having reactivity problems, it's probably just managing the decay heat, and now the radiation leaks, that's the problem. "Just" is a relative word, here, of course.

Boiling water reactors are simpler, cheaper, but generally aren’t made anymore because they are perceived as being less safe. That’s because the exotic coolant in the pressurized water reactor can contain boric acid which absorbs neutrons and can help (or totally) control the nuclear reaction. You can’t use boric acid or any other soluble boron-laced neutron absorbers in a boiling water reactor because doing so would contaminate both the cooling system and the environment.

He's completely wrong about industry adoption of BWRs. There are two BWR's planned to be built in the US (along with 3 or 4 PWRs), and I believe that China has contracted with GE for a few as well (along with 4 Westinghouse PWRs and maybe a few Areva ones too).

PWRs are preferred largely because of their higher power densities (a BWR core that produces the same power must be larger) and simpler nuclear calculations and control strategies (two-phase flow makes calculations much more difficult, and it's harder to calculate correct positions for control blades (whose effects are highly localized) than it is to calculate the correct boron concentration (whose effects are smeared over the whole core)). However, now that computers are faster and us nuclear engineers no longer have the excuse of slow computers to hide behind, PWRs are looking to move away from relying on Boron concentration as the main form of control (the Westinghouse AP1000, specifically, relies much more on rod movement than the AP600), because of the cost of performing regular boron dilutions.

He's right that BWRs are simpler and cheaper - about half the moving parts.

20.Why cigarette packs matter (badscience.net)
79 points by baha_man on March 12, 2011 | 35 comments
21.Engadget's Top Editors Topolsky and Patel Exit From AOL's Giant Tech Site (allthingsd.com)
77 points by moses1400 on March 12, 2011 | 21 comments
22.Google at their best. Facebook at their best. (bryce.vc)
75 points by razin on March 12, 2011 | 15 comments
23.Former nuclear reactor operator on Fukushima risks (theenergycollective.com)
73 points by transmit101 on March 12, 2011 | 14 comments
24.Sun.com Will Disappear After June 1 (sun.com)
73 points by there on March 12, 2011 | 41 comments

Just last night I used search to ask a question (where to go to watch planes take off and land at SFO) and found the answer on a Yahoo Answers page.
26.IPad 2 Wi-Fi Teardown (ifixit.com)
69 points by nirmal on March 12, 2011 | 27 comments
27.The thousands of startups today that are pitching... (bryce.vc)
66 points by liuhenry on March 12, 2011 | 16 comments
28.Stack Exchange CEO: "Nobody Wants To Find Yahoo Answers In Their Search Results" (techcrunch.com)
66 points by thankuz on March 12, 2011 | 46 comments
29.AMD needs 1000 Developers with Linux Skills (dice.com)
65 points by Newky on March 12, 2011 | 27 comments
30.Study: Diet May Help ADHD Kids More Than Drugs (npr.org)
64 points by squarepeg on March 12, 2011 | 39 comments

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