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Comment: Couple problems (Score 4, Informative) 139

by Solandri (#46784285) Attached to: MIT Designs Tsunami Proof Floating Nuclear Reactor
Mind you, I am pro-nuclear.

Meanwhile, the biggest issue that faces most nuclear plants under emergency conditions â" overheating and potential meltdown, as happened at Fukushima, Chernobyl, and Three Mile Island â" would be virtually impossible at sea."

Simply being at sea doesn't prevent the cooling problem. Remember, Fukushima was right on the ocean. The problem is that the cooling system has to have at least two loops. An internal loop of coolant (usually water, though salt has also been used) actually travels inside the reactor. Consequently it picks up some residual radioactivity from being exposed to all those neutrons flying around. You cannot just use this single loop for cooling, or else you're releasing this radioactive coolant into the environment.

A second external loop of coolant cools the internal loop via a heat exchanger. This external loop picks up nowhere near as much radioactivity, and the coolant (water) is safe to dump back into the environment.

If it were just one loop, you could come up with a clever design using thermal expansion to make the water flow through it to provide passive cooling in the event of a pump failure. But with two loops (and the inner loop being closed), you're pretty much reliant on active pumping to remove heat from the reactor core. The problem at Fukushima was that power to these pumps failed, and backup generators designed specifically to supply power in that scenario were flooded and their fuel source contaminated.

I don't see how putting the plant on a floating platform helps in this scenario, unless you're willing to open up the primary cooling loop to the environment and just dump water straight into the reactor (with the resulting steam carrying both heat and radioactivity out). Which was pretty much what they ended up doing at Fukushima. If they'd done it before the cladding on the fuel rods melted, we'd only be dealing with a small amount of radioactive water (deuterium, tritium, etc) being released into the environment as steam, instead of fission byproducts being directly released. So I don't see how being by vs on the ocean makes any difference for this scenario.

Maybe you could design the steel containment sphere to act as a heat sink, allowing sufficient cooling when submerged? But the containment's primary job is to contain what happens inside. That's why it's a sphere - it encloses the largest volume for the least amount of material and surface area, and its mechanical behavior under stress are very easy to predict. This is precisely the opposite of what you want from a heat sink. You want the most surface area for a given enclosed volume. Which makes me suspect that the steel containment could only operate as a heat sink if you're willing to compromise its protective strength somewhat.

The other problem I see is that putting it out at sea hinders accessibility. Meaning more mundane events like a fire, which are trivial to handle on land, become much more problematic at sea.

Comment: Re:RAID? (Score 2) 239

by Solandri (#46782697) Attached to: SSD-HDD Price Gap Won't Go Away Anytime Soon
This. Most people still incorrectly concentrate on sequential read/write times. SSDs are only about 4x faster by that metric - 550 MB/s vs 125-150 MB/s.

Where SSDs really shine are the small, rapid read/writes. If you look at the 4k r/w benchmarks, a good SSD will top 50 MB/s 4k speeds, and over 300 MB/s with NCQ. A good HDD is only about 1.5 MB/s, and maybe 2 MB/s with NCQ because of seek latency - the head needs to be physically moved between each 4k sector. That 100-fold difference is what makes SSDs so much faster in regular use, not the sequential r/w speeds.

Comment: Re:Useful Idiot (Score 3, Interesting) 351

We've shown Americans how we deal with leakers by our handling of Bradley/Chelsea Manning. Snowden had no choice but to go to our enemies for asylum.

Please don't compare Manning to Snowden. Manning copied everything he could get his hands on and released it all without any consideration for whether or not it had a valid reason to be secret. He threw the baby out with the bathwater. Snowden has been careful to release only the things he feels violated the oath he and others took to the U.S. Constitution. One is a vandal. The other is a genuine whistleblower if not a patriot and hero.

For him to be a hypocrite, he'd have to spy on americans. If he has to do propaganda for the Russians to survive, then who cares? It's the Russians' problem, not ours.

I dunno why you think he has to spy on Americans to be a hypocrite. By doing propaganda for the Russians, he is affirming that sometimes you have to compromise your lesser values in order to protect greater ones. That's exactly what he's whistleblowing the U.S. government for doing - compromising Americans' privacy in order to (in their best estimation) protect their safety. If you actually listen to what Feinstein and others who defend these programs are saying, they're not evilly rubbing their hands together while cackling with glee that they're violating the Constitution. They implemented these programs because they genuinely thought the benefit (improved safety for Americans) was worth the cost (warrant-less searches and degradation of privacy).

What differentiates what he's doing IMHO is that if something is written in the Constitution, that kinda implies that it's an uncompromisable value. That you cannot violate Americans' 4th Amendment rights even if doing so would result in greater safety. Exceptions can be made during martial law and war, but no such declarations were made (unless you consider the war on terrorism to be a real, declared, and unending war).

Comment: Re:As a SATCOM professional... (Score 1) 51

by DigitAl56K (#46780121) Attached to: The Dismal State of SATCOM Security

LDR services like Inmarsat were never meant to be secure. Now if this was about AEHF that would be news.

I'm pretty sure they're meant to be at least secure enough that Joe Shmoe couldn't take them over with a text message or a known hardcoded credential. Well, unless you can point someone at this list of vulnerabilities and say "it's not meant to be secure", and still make your sale, of course.

Comment: Re:Nonsense (Score 2) 276

by Antique Geekmeister (#46777673) Attached to: Ask Slashdot: System Administrator Vs Change Advisory Board

> Any remotely well organised IT department will have processes for handling both emergency deployments and retrospective approval

Not when the architect is offline and is needed for every significant change. If there is going to _be_ a policy, a manager needs to be ready to enforce it, or it's going to be everyone making up their own undocumented and impossible to synchronize policies.

Comment: Re:Subtle attack against C/C++ (Score 1) 188

by bzipitidoo (#46776621) Attached to: The Security of Popular Programming Languages

I wonder if zeroing out memory can go even deeper than the OS. Like, why not have RAM that can zero itself on command? Just turn off the DRAM refresh for a fraction of a second, and viola!

Memory moves have been made much faster by bypassing the CPU, for instance with hard drives with the DMA mode rather than PIO mode. So they are using a DMA from a /dev/zero device or more like a 4k page of zeroes to a range of memory? What you're describing sounds like an excellently lazy method. Zero newly allocated the memory when it is the object of a pagefault, not eagerly when allocated. Though nowhere near as bad as a PIO (or just PO?) method of pushing zeros out of the CPU and into memory, I'm guessing that is still a small performance hit. Is it?

Comment: Re:Rewarding the bullies... (Score 1) 777

1. Kids shoot up schools. Why schools? Why not shopping malls before Christmas or movie theaters during blockbuster premiers?

1) Kids are in school 30%-40% of their waking lives. It's normal that a disproportionate amount of everything that happens to them happens at school.

2) They don't really shoot up schools. Statistically a kid is much more likely to be shot outside of school than in school. It's just that "school shootings" have become a thing for the media, so the threshold at which one will become a national news story is much lower than, say, a bunch of gang members shooting each other in a drive-by shooting, or a bunch of teens being killed in a car accident. Despite the impression you get from the media, if you want your kids to be safe from shootings, you're better off sending them to school. Normalize for the time they spend in school (#1 above) and statistically they're even safer.

3) When a shooting happens at a school, the vast majority of victims are other kids simply because of the demographics of the people in the area. So it gets classified as kids shooting kids. When a shooting happens outside of a school, the majority of victims are adults. So it gets classified as a "regular" shooting incident even if a significant number of kids were victims

Comment: Re:Dead? (Score 2) 109

by Solandri (#46772541) Attached to: Intel Pushes Into Tablet Market, Pushes Away From Microsoft
This is just the flip side of Windows RT. Microsoft developed RT to hedge their bets. If the market stayed with x86, they could sell regular Windows. If the market switched to ARM, they could sell Windows RT. RT didn't need to be successful, it just needed to be there.

Now Intel is doing the same - they're hedging their bets. If the market stays with Windows, they can can sell CPUs for Windows machines. If the market switches to Android or whatever OS over Windows, then can sell CPUs for those machines.

That's really what the phrase "Wintel is dead" means. It doesn't mean there are no more Wintel boxes being made. It means the Microsoft-Intel partnership is no longer an exclusive partnership as if they were one company. They're starting to treat each other as just another disposable business partner.

Comment: Re:Not a market back then (Score 1) 239

by Solandri (#46772357) Attached to: Nokia Had a Production-Ready Web Tablet 13 Years Ago
This. The tablet was held back for nearly a decade by Intel and Microsoft insisting that it had to be a convertible laptop. Microsoft wanted to make sure each tablet sales was a Windows license sale, and Office too if they could. Intel wanted to make sure each tablet sale was was an x86 CPU sale, and a high-end CPU too if they could. Consequently, the tablet PC market stagnated at fewer than 100,000 sales per year for close to a decade.

The real technology that led up to tablet market space wasn't the smartphone; it was the netbook. Suddenly people realized that most of the stuff they did on laptops (email, web browsing, myspace/facebook, listening to music, watching movies), they could do just fine on devices which didn't run Windows and didn't have a PC-like CPU, and consequently could be cheaper than a laptop, not more expensive like tablet PCs were.

Comment: Re:Superior pilots (Score 1) 100

by TheLink (#46770667) Attached to: Your <em>StarCraft II</em> Potential Peaked At Age 24
Check your monitor, mouse and keyboard latency. A decade earlier you might have been using a CRT with lower latency than a slow LCD monitor.

In my experience add them all up and it can make the difference between having a < 200ms response time and a > 250ms response time.

Try digging out an old CRT if you have one and see if it makes a difference in your reaction times on those reaction time websites.

Comment: Re:I have serious doubts.. (Score 1) 100

by TheLink (#46770499) Attached to: Your <em>StarCraft II</em> Potential Peaked At Age 24
Even so, Starcraft also rewards those who micromanage units - like a Terran floating a building as bait to distract unmicromanaged enemy troops while the Terran troops destroy the enemy. All while
micromanaging other stuff and building.

The real life command and control interfaces you mention assume the units won't need to be micromanaged.

Comment: Re:sickening (Score 2) 777

If you want your kid to learn to stand up for himself, would you pay a couple of other kids to beat him up until he finds the nerve to punch back, or would you send him to a self defence class? The first is likely to end in physical or psychological trauma, the second more likely to instil confidence as well as help keep potential bullies off his back.

What schools like these are doing is teaching him that his place in the hierarchy is being the classroom punching bag, and that he will be punished if he fights back or complains. Yes, life can be like that too, but only if you let it. School should be teaching him how to deal with such issues, not forcing him to suck it up.

Comment: Re:Rewarding the bullies... (Score 4, Insightful) 777

And, what if this kid commits a Columbine-esque revenge scenario?

Appropriately, the page with TFA has an ad encouraging me to "Win an AR-15 from Sebastian Ammo". Google is getting scary...

As for the action taken by the school, one really has to wonder as to what kind of cretins make up the school administration. And what they could possibly have hoped to achieve by filing charges, other than a nasty (and well deserved) publicity backlash? Although for a society run by lawyers, that's perhaps what one would expect. Squeaky wheel gets a beating, and a teenager gets hauled in front of a judge on charges of "disorderly conduct" in a school. Seriously... Can any of the officials involved in this case look in the mirror and tell themselves that they are doing the Right Thing?

Comment: Re:Well, who better to... (Score 2) 98

by JaredOfEuropa (#46765443) Attached to: Google Looked Into Space Elevator, Hoverboards, and Teleportation
I think you hit the nail right on the head: besides projects they can undertake themselves if a study shows they are more or less feasible, they are looking for longer term investment opportunities. The article didn't mention any of that, but it seems reasonable that Project X is not just about turning ideas into products, but also a factory of patents, and a way to get the jump on competitors when it comes to buying companies that do actual research into promising new tech.

Comment: Re:Nothing new here (Score 1) 213

by JaredOfEuropa (#46765061) Attached to: How 'DevOps' Is Killing the Developer
I see plenty of this, but it rarely has me worried. You have to take these Excel / Access "applications" for what they are: they typically exist as job aids for single persons or small teams. Is it pretty or sustainable? No: if the author of the application leaves and something needs to be changed or fixed, no support org will touch it with a 10 foot pole. This is where the difference between risk avoidance and risk management comes in. Risk avoidance means shaking your head in horror, and removing Access and VBA from workstations. Risk management means educating people about when it is appropriate to use such a tool, and when it isn't (like time or mission critical situations). Oh, and if the software does break and the original programmer has left, just hire a contractor to fix things. In my experience, they rarely need more than a few days for a fix or a simple change. Sometimes I just do it myself.

Why do we allow this? Because it is extremely cost effective, and it rarely causes trouble.

Nothing is easier than to denounce the evildoer; nothing is more difficult than to understand him. - Fyodor Dostoevski