Catch up on stories from the past week (and beyond) at the Slashdot story archive


Forgot your password?

Comment Re:So what (Score 1) 340

The problem is Congressional mandate: Any storage cask must survive 10,000 years without leakage (yeah, citation needed, looking for it). Staying intact through train wrecks and 30 foot drops is trivial - can you build a device that will withstand 10,000 years of erosion/corrosion/whatever? And be recoverable/countable for the duration... There are lots of technically possible disposal methods - I personally like the "drop it into the deep ocean trench off SoCal." As the plates move (Farallon plate going into subduction), the waste just goes down into the bowels of the earth where it came from. Problem? Congress wants it countable - and once it goes down, you can't get it back.

Comment Re:GPS transmitters can be faked/set up (Score 1) 279

Ah, not quite. You are describing Differential GPS, or DGPS. Your center-of-the-track receiver sits at a known location. It calculates a GPS posit based on satellite inputs, and figures out the error because it knows where it is. You then broadcast that error signal to any DGPS receiver within reach. The other receivers use their own calculated GPS posit + broadcast error signal to give greater precision. Just about every major port or waterway in the US does this.
Could you set up a fake posit? Maybe - if you can broadcast enough satellite-sounding signals to convince a reciever that it has a good lock. Most of them want at least 4+ to produce a position.

Comment Re:No redundancy (Score 1) 247

Yes, normal = all four pumps running. In a PWR, your analyzed safety margins generally say "percent total flow through the core must be equal to or greater than total percent power."

So to get full output from the plant (100% power) you need 100% flow - all four running. One pump trips, and total flow goes to ~82% (hydraulics, pump heads, etc. Not a simple 75%.)

But power hasn't changed yet. 100% > 82%, automatic trips kick in and shut the plant down. You haven't damaged anything because the designed safety margins and trip responses take the transient into effect.

Can you run on three pumps? Sure, just not at full rated output. And since your job is to produce as much electricity as you can, the typical civilian plant is binary - either shut down or 100%.

Comment Re:What does the US Navy use . . . ? (Score 1) 308

USN is quickly moving away from INMARSAT. Too slow for our needs today - at this point, only a few ship classes still use it (FFG, some amphibs). Everyone else is using an EHF/SHF link to the Defense Satellite Communications System (DSCS) - several geostationary birds parked over the equator that allow T-1+ access. We share that out based on who is in the area - the big guys (carriers, etc) stay close to T-1 bandwidth, fairly typical for a destroyer-size ship to have something like 512 or less. We have several networks that ride over that data path. But that does need a pair of big antennas under gyro stabilization....since the best setup is a pair of primary SHF with automatic failover to the EHF pair (aimed at a different bird).

Comment Missing the point (Score 4, Interesting) 312

Their real point is successful intercept of the entire missile body != intercept of the warhead, not that the intercept missed entirely. Of course, the SM-3 system has actually done an exo-atmospheric intercept (failing satellite over the Pacific).... (speaking as someone who actually used to run a ship capable of doing this.)

Comment Not quite..... (Score 1) 196

Great quote from the UK article: "Since buyers are likely to have a lot of disposable income and not much sense...." TFA is wrong - malware is aimed at the Winbloz boxen, by offering a download of a "new iTunes" program. Macs and iPads are not impacted.

Comment Re:If you have physical access to a machine... (Score 1) 233

At the moment, this is being used as a defense-against-the-user, not against intruders. Problem came up when malware got loaded onto a clean network via a USB drive, unknown to the user. Many of the military networks are set up to protect against intrusion from the outside, with decent firewalls/etc between the internet and the 'inside' network. The USB used by a stupid user obviously jumps the the worm/trojan/whatever is loose on the inside. Network policies already say "don't use the same drive at home and at work"...but if everyone followed the rules, we wouldn't have malware....can't easily kill the USB ports since most of the keyboards/mice/etc are USB-only. Essentially, all this thing does is provide a way to sweep the networks and check for compliance. File transfers between classified and unclassified systems are a completely different problem.

Slashdot Top Deals

To be is to program.