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Comment Re:So Let Me Get This Straight (Score 1) 71

Exchange Server is one of the killer points, yes. The other one is Domain Login with the attendant domain-wide security model. As a *nix booster, I must say those two continue to absolutely show up *nix to this day. Those two give more than enough of a "point".

Both Mac OS X and RedHat Linux have answers to both domain login and domain-wide security. The Linux implementation is somewhat less robust (i.e. it's possible to escape exclusion groups, and there's no external group membership resolver like there is on Mac OS X, so there's still the 16 group limit), but it at least is a proof by existence that the claim is wrong. And you can always install the Samba implementation manually on any Linux or BSD box.

If you want to get technical, had Windows not added the proprietary field, we're just talking a KDC implementation, as in Heimdal Kerberos, or before that, MIT Kerberos, and that's been around since Project Athena, which means early 1980's, which means over 30 years. Microsoft's implementation was 1995 or so, and it was the late 90's before they made it non-interoperable with the proprietary field, so they are predated by at least a decade.

Kerberos was interesting, in that it abused the setgroups() and cr->ngroups to store the Kerberos key in the last two groups field, but at that point you were not really using groups anyway (since you were using remote Andrew FS or similar, and it was doing server side credentials enforcement).

So TL;DR: they absolutely did not, and do not, "show up *nix".

Comment Re:sunfire / in my stellerator / makes me... happy (Score 1) 96

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 ;)

Comment Re:Does it affect functionality at all? (Score 1) 358

Most of us work in situations where data is either privileged from a business perspective or legally protected. Even if actual private data is not being collected, patterns and routines can steal lead to actionable leaks. In as much as we expect to remain competitive and work within the law, potentially this does effect functionality.

Comment "Does the Obama Administration..." (Score 1) 92

"Does the Obama Administration..."

Yes, they understand that.

President Obama is invested in the Vanguard 500 Index Fund as one of his largest holdings, apart from bonds and T-bills -- Source: http://www.davemanuel.com/pols... -- which in turn is invested in:

Telecoms: AT&T Inc., Verizon Communications Inc., Comcast Corp. Class A
Oil companies: Exxon Mobil Corp., Chevron Corp.
Pharma companies: Johnson & Johnson, Pfizer Inc., Merck & Co. Inc., Gilead Sciences Inc., Allergan plc, Amgen Inc.,
Banks: Wells Fargo & Co., JPMorgan Chase & Co., Citigroup Inc., Visa Inc. Class A
Healthcare problem companies: Philip Morris International Inc., Altria Group Inc., McDonald's Corp., Coca-Cola Co., PepsiCo Inc.
Healthcare solution companies: UnitedHealth Group Inc., CVS Health Corp., Medtronic plc

Among others -- Source: https://personal.vanguard.com/...

So perhaps this explains the issues he's interested in, and the things he votes and advocates for and against.

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:Social Justice Twitter (Score -1) 78

Typical SJWNPAT (my acronym for SJW Normal Person Anti-Terrorist), all Twitter is doing is censoring people for criticizing Ethics in Western society. Sure, some people have claimed in ISIL's name to have murdered a few people here and there, but first of all THOSE people they supposedly "murdered" are professional victims and their claims of being murdered are highly suspect no matter how many videos we produced of them being beheaded and threads on /r/WesternSocietyInAction you can point at where every laughed at the Beta Cuck Infidels. And secondly, just because they said they were ISIS doesn't mean they were, I mean, it's a hashtag, you can't police that. You can't blame some guy on Twitter who is just concerned with Ethics and sends a few rape threats to Hillary Clinton THAT ARE CLEARLY NOT SERIOUS with some other guy who murders people because that's totally unfair. And also (continued on thread 94)

Submission + - Women in biopharma decry booth babes in letter (biocentury.com)

sandbagger writes: A group of women in the pharma industry have signed an open letter asking that the practice of models at events be halted because it's demeaning women. Tech companies have gone through this in fits and starts for years and slid back despite promises.

Comment Re:sunfire / in my stellerator / makes me... happy (Score 1) 96

So on average the fission reactor material only has about 10% of its atoms displaced over the lifetime, while the fusion reactor would have, on average, every atom displaced hundreds of times over the lifetime.

How can you make generalized statements like that? Cross sections vary by many orders of magnitude Fission reactors are generally made of steel, which is hardly setting any records in terms of low cross sections. The smaller the reactor, the less material you have to replace, and the more expensive the material you can use. And being "displaced" is not a fundamental universal material property effect, it depends on how the material responds to radiation damage, which varies greatly. Generally materials respond better at high temperatures (annealing), and fusion reactors operate of course at far higher temperatures than fission reactors.

I have trouble seeing how one would consider neutrons per square meter to matter more than neutrons per MeV. Because neutrons determine what you're going to have to replace, and energy determines how much money you get from selling the power to pay for said maintenance. You can spread it over a broad area and do infrequent replacements, or have it confined to a tight area and do frequent replacements, the same amount of material is effected. Some degree of downtime for maintenance is normal in power plants - even "high availablility" fission plans still only get ~85% uptime.

Submission + - Speeches That Earned Clinton Millions Remain a Mystery (go.com)

mdsolar writes: Hillary Clinton told voters in the latest Democratic debate there's "hardly anything you don't know about me."

Just minutes later, she got tangled in a question about a part of her resume that is an enduring mystery.

In the 18 months before launching her second presidential bid, Clinton gave nearly 100 paid speeches at banks, trade associations, charitable groups and private corporations. The appearances netted her $21.7 million — and voters very little information about what she was telling top corporations as she prepared for her 2016 campaign.

What she said — or didn't say — to Wall Street banks in particular has become a significant problem for her presidential campaign, as she tries to counter the unexpected rise of Democratic rival Bernie Sanders. He's put her in awkward position of squaring her financial windfall with a frustrated electorate.

Asked in the debate — and not for the first time — about releasing transcripts of those speeches, she said: "I will look into it. I don't know the status, but I will certainly look into it." She added, "My view on this is, look at my record."

Comment Re:Power efficiency is good in some places, not al (Score 1) 286

John Cook (put his blog in your RSS feed if you don't already have it) made a very good point recently: The speed gains from Moore's Law are dwarfed by the speed gains from algorithmic improvements. And unlike Moore's Law, we're not yet seeing a limit approaching for better ways to solve stuff. The post in question: http://www.johndcook.com/blog/...

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