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Submission + - Ask Slashdot: Surge Protection for International Travel?

gaiageek writes: As someone who has lost a laptop power supply (and thus use of the laptop) due to a late-night power surge while traveling in a developing country, I'm acutely aware of the need for surge protection when traveling abroad. While practically all laptop and phone power adapters these days are voltage auto-sensing 100V-240V compatible, most so-called "travel" surge protectors are restricted to either 110V or 220V. Given the space and weight constraints of carry-on only travel, I'd like to avoid having to carry two separate surge protectors knowing I may go from Central America (110V) to Southeast Asia (220V). Strangely, laptop specific surge protectors typically are 100V-240V compatible, but this doesn't provide protection for a phone or tablet that requires the original power supply (can't be charged from a notebook USB port).

Is there really no solution out there short using a 110V-240V notebook surge protector with an adapter to go from a "cloverleaf" notebook plug to a 5-15R (standard US) plug receptacle?

Comment Re:sunfire / in my stellerator / makes me... happy (Score 1) 97

Fast neutron cross scattering sections in the couple MeV range barely vary over more than the range of 1-10 barns

1-10 barns is, of course, by definition, an order of magnitude. There is a massive difference between 10 barns and 1 barn. Tenfold, to be precise. ;)

More to the point, you can't just combine all cross sections like that. The energy imparted from an elastic collision isn't the same as from an inelastic collsiion, which isn't the same as an (n, gamma), and so forth. Elastic collisions are particularly low energy, particularly the higher Z the target. Taking them out of the equation yields much greater differences between materials in the range of a couple MeV. The upper end of the neutron energies are "somewhat" similar (up to about one order of magnitude), but down below 6 or 7 MeV or so there's quite a few orders of magnitude difference.

Likewise, total cross sections have no bearing on the accumulation of impurities in the material. The particular cross sections are relevant not only in terms of reaction rate, but also what sort of impurities you tend to accumulate and what effect they have on the properties of the material. Which of course varies greatly depending on what exactly they are.

Integration of annealing cycles into blanket design is not brought up enough in some design studies, but is a consideration to help

It's not a side issue, it's a fundamental issue to the design of a material designed for high temperature operation under a high neutron flux.

Blanket design is extremely constrained by tritium breeder ratio to ensure more tritium is produced than used, which squeezes volume allowed to be used by coolant, ... but they have much lower neutron flux to worry about. Gen 4 reactor designs are in the 500-1000 C temperature range, exceeding in some cases what is thought reasonable for fusion blanket design. ... Blanket replacement is considerably more complex than fuel replacement in a fission reactor

Perhaps they've been heading in a different direction since I was last reading on the topic, but I was under the impression that a prime blanket material under consideration was FLiBe. Which operates in a temperature range of 459-1430C, and is its own coolant. That doesn't change what the first wall has to tolerate, but as for the blanket itself, you have no "structural properties" to maintain, and cooling is only limited by the speed that you can cycle it.

The last paper I read on the subject also suggested that for breeding purposes one needs not only beryllium (they were reporting really poor results with high-Z multipliers), but the optimum ratio (to my surprise) worked out to be significantly more beryllium than lithium. So building structural elements out of beryllium serves double purpose, you don't have the excuse of "I need to use steel because it's cheaper" - you need the beryllium either way. It's strong, low density, similar melting point to steel, but retains strength better with heat, and highly thermally conductive. Beryllium swelling from helium accumulation stops at 750C+ as helium release occurs. So pairing a beryllium first wall with a FLiBe-based blanket seems like a very appropriate option.

Please don't get me wrong, I'm not at all disputing the great amount of engineering work left to do. I'm just more optimistic that appropriate solutions will be found. Perhaps I'm just naive in that regard ;)

Submission + - Snowden Leaks Cost Pulitzer Winning Journalist W.H. Security Clearance, Job (businessinsider.com)

An anonymous reader writes: Pulitzer prize-winning journalist Ashkan Soltani was recently detailed to the White House Office of Science and Technology Policy from a position at the the Federal Trade Commission. Former Google executive and White House chief technology officer Megan Smith extended a warm welcome. His portfolio at the White House included privacy issues, data ethics, and outreach to the technical community, among others. His drug test was complete, and the FBI investigation for his clearance was under way, when the wheels came off. His clearance was denied. Ashkan's move to the White House surprised some when it was announced due to his history. Ashkan had worked at the Washington Post where he helped analyze and safeguard the Snowden NSA document dump. A technologist at the ACLU noted that Ashkan had published many stories that probably irritated US intelligence officials. Government organizations have previously warned government employees to not access classified information made available in the media. Nobody is directly stating this is the reason, but the subtexts seem clear enough. Ashkan intends to leave Washington and head back to the west coast.

Comment Re:Decades of makware (Score 1) 36

Some could. Amigas (and Macs too I believe?) would automatically pop up an icon for floppies when they were inserted, without needing to do anything else.

While those absolutely are technically "personal computers", everyone understands "PC" to mean "IBM PC or compatible". And yes, both Amigas and Macs had floppy detect. Actually, it was technically possible to do it on the PC as well, and ISTR some programs actually doing it. The solution to the training problem is pathetically obvious (as evinced by the fact that I figured it out while reading TFA which I just google'd) which is to train the system the first time the user successfully reads a floppy disk, and thus you know that there's a disk in the drive. But... Microsoft

Submission + - GitHub is undergoing a full-blown overhaul as execs and employees depart (businessinsider.com)

mattydread23 writes: This is what happens when hot startups grow up. CEO Chris Wanstrath is imposing management structure where there wasn't much before, and execs are departing, partly because the company is cracking down on remote work. It's a lot like Facebook in 2009. Business Insider has the full inside story based on multiple sources in and close to the company.

Submission + - Listen to a Hawking lecture on Black Holes! (bbc.co.uk)

An anonymous reader writes: The BBC has now put the second of Stephen Hawking's Reith Lectures up on their web site, with accompanying illustrations. It's not 'All you ever wanted to know about Black Holes', but it's an easy introduction to some of the latest thinking on them...

http://www.bbc.co.uk/news/scie... refers...

Comment Re:freedom (but only for those we like) (Score 1) 85

This. Exactly this.

The correct answer to people spouting bullshit is to call out their bullshit. Don't silence them by squelching them, silence them by showing them that they are wrong, that they are not the "vocal minority that dares to say what others only think", but that they are a loudmouth few who babble what everyone else knows is BULLSHIT.

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