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Seagate Ships First 8 Terabyte Hard Drive

AJWM Re:if 1 drive full, raid. Dual read write armature (270 comments)

Back in the day, my college campus mainframe, a Burroughs B6700, had (in addition to its more conventional "disk pack" drives) a head-per-track (HPT) drive. The disk was several feet in diameter and the whole surface was covered with read/write heads (they didn't need to move).

Can't find specs on the B6700 version, but here's a blurb about the older B5500 version (from http://www.retrocomputingtasma...)

The powerful advanced systems concepts of the Burroughs B 5500 are fully complemented by the revolutionary Burroughs On-Line Disk File subsystem. With its "head-per-track" design, the Disk File provides all-electronic access to any record throughout the file in an average of 20 milliseconds.

        File organization, programming, and use are simplified because access is entirely by electronic switching, with no moving arms, card drops, or the like. Each record segment is equally available regardless of physical location on the disks. Multiple segments can be transferred with a single instruction.

        Module size is four disks totalling 9.6 million alphanumeric characters of information capacity. Up to 100 of these modules may be used with the Burroughs B 5500, effectively extending the memory of the computer systems by almost a billion characters. Transfer rate is 100,000 characters per second.

11 hours ago

TechCentral Scams Call Center Scammers

AJWM Re:Is he a senior? (232 comments)

As others below have noted, plenty of old fogies remember The Terminator, its sequels, or The Sarah Connor Chronicles (watchable only for Summer Glau).

I have to confess though that my first thought was to wonder if he was related to John Bigboote ("that's Bigboo-tay!") or John Smallberries.

12 hours ago

TechCentral Scams Call Center Scammers

AJWM Re:Not so sure it's harmless (232 comments)

I only got them to stay on the line for about 15 minutes. When he told me to press the Windows key ("The what?" "The key with a flag picture on it") I said "My key has a picture of a penguin on it, does that make a difference?"

He hung up.

12 hours ago

If Java Wasn't Cool 10 Years Ago, What About Now?

AJWM Re: Nope (493 comments)

Back in my (pre PC) college days, COBOL was big in business but wasn't taught or used by anyone in the Computer Science department. If you wanted to learn COBOL, those courses were offered through the school of Business.

And APL was taught by the department of Mathematics, to the extent that APL packages were used in the statistics classes.

Computer science classes weren't about teaching programming languages (we probably went through a dozen or more, from Algol and assembler to Lisp and Simula and Snobol -- we were expected to learn them ourselves depending on the assignment), but about how to think about programming (and operating systems and so on).

2 days ago

Processors and the Limits of Physics

AJWM Lightspeed (168 comments)

Yet another reason to find a way around the speed of light.

Actually I've always said (jokingly) that if anyone does find a way to go FTL, it'll be the computer chip manufacturers. In fact Brad Torgersen and I had a story to that effect in Analog magazine a couple of years ago, "Strobe Effect".

about two weeks ago

Passport Database Outage Leaves Thousands Stranded

AJWM Re:Here's the problem... (162 comments)

Or worse, they're running SQLServer on Sun boxes...

about a month ago

Favorite "Go!" Phrase?

AJWM Let's light this candle! (701 comments)

Although actually the "let's" wasn't part of Alan Shepard's original phrase. (In a similar vein, "Get those scientists away from that rocket and shoot it!".)

Another favorite: "Let's roll!"

Least favorite (or most hated): "Let's do this". Talk about hackneyed and overused phrases.

about a month ago

Favorite "Go!" Phrase?

AJWM Re:Misquote in #1 (701 comments)

In the Apollo program -- at least, with Saturn V launches -- it's "Ignition sequence start" at T-7 seconds. Those F-5 engines had a complicated ignition sequence which took several seconds just to get the dang things lit. (The pre-burners which turned the propellant turbopumps had to be lit first, and the RP-1 propellant (essentially kerosene) was also used as the hydraulic fluid for gimballing the outboard engines, so had to be pressurized.)

With the Shuttle they started main engines a couple of seconds before T-0 to give them time to come up to power and ensure that they were running properly before igniting the SRBs. Once the solids were lit everything was along for the ride until burn-out (or explosion, as with Challenger).

about a month ago

NASA Approves Production of Most Powerful Rocket Ever

AJWM Re:I dont see a problem here (146 comments)

I would much rather them use existing tried tech and incrementally advance them rather than try a radical new design.

Except that they're not. Those solid boosters? They're "based on" Shuttle SRBs, not identical to them. Several segments longer, meaning higher internal pressures, different burn characteristics, etc. If you don't think that's going to take extra years of testing, there are several bridges I'd be happy to sell you.

Ditto for any other technologies that they're basing stuff on rather than reusing identically.

The SLS isn't also known as the "Senate Launch System" for nothing. NASA's role should be to try radical new designs, not serve as a conduit for senators to shovel pork to their constituents.

about 2 months ago

New Class of Stars Are Totally Metal, Says Astrophysicist

AJWM Re:Star? (119 comments)

Yep. Carbon, nitrogen, oxygen .. all metals. To an astrophysicist, we're not made of meat, we're made of metal.

(Okay, there's a fair bit of hydrogen in our mix, too.)

about 2 months ago

Brownsville SpaceX Space Port Faces More Regulatory Hurdles

AJWM Re:Texas has regulations? (78 comments)


A launch from Florida (in an easterly direction) doesn't look like it might be an attack on Cuba; a launch from south Texas does (or could). The political and technical situations are a bit different today.

Also, spreading the pork around to multiple states/congressional districts. Texas got the facility in Houston.

Oh, and what open water is to the west of Brownsville? ;-)

about 3 months ago

Updating the Integrated Space Plan

AJWM Re:Sorry, but this is silly (65 comments)

As the saying goes, no (battle) plan survives contact with the enemy. That doesn't mean such a plan has no use whatsoever.

An 'Integrated America Plan' or an 'Integrated Computing Plan' would of course be ludicrous in hindsight. (Just as is the original Integrated Space Plan). But such plans have the power to inspire people. To make people think "hey, I see a better option over here". To encourage people to make it so. To dream things that never were and say "why not?"

Sure, if we had cheap access to space there'd be a lot more people making their own plans and going out and doing it. Maybe this plan will help inspire the next generation's Gary Hudson, Elon Musk or a non-fictional Delos D. Harriman.

(Disclaimer: I've probably still got a small stack of the original ISP poster in my basement. My ex used to sell them through her (long defunct) Space Pioneers business.)

about 3 months ago

What qualifications should the 'driver' of a fully autonomous car need?

AJWM Depends whether it has manual override. (301 comments)

If it's truly autonomous, with no manual override (or the override can be locked out and proved to be locked out) then why have any restrictions at all? Of course then the rider is really a passenger, not a driver.

If the car has a way to let the passenger take manual control and override the autopilot, then the passenger has become a driver and should be properly licensed.

While I don't discuss the licensing issues, my book The Reticuli Deception (set about 100 years from now) has several scenes involving both completely autonomous (sole occupant darkens the windows and takes a nap) and not (driver overrides the computer to deliberately cause a collision with the guy tailing someone, then escapes by having arranged for a rental car to drive itself to the next block and be waiting for him). (That's only a minor spoiler, most of the book takes place off-Earth. Caveat, it's a sequel to The Chara Talisman, which come to think of it has one scene with an autonomous taxi.) </blatantplug>

about 3 months ago

Electric Stimulation Could Help You Control Your Dreams

AJWM Re:40 hz of current? (138 comments)

>40 hz of current?

Sure, at a frequency of 30 mA for about 0.5 volt-hours.

about 3 months ago

Mathematical Model Suggests That Human Consciousness Is Noncomputable

AJWM False assumption? (426 comments)

Who says memory retrieval is non-lossy? It's an organic process, of course it's lossy. Our brains just make shit up to fill in the gaps.

The stuff we retrieve frequently is slightly less lossy because it gets refreshed (somewhat) when we remember it (sort of remembering that we remembered it).

And our brains are very good at making shit up to fill in the gaps, almost too good.

about 4 months ago

Ask Slashdot: Practical Alternatives To Systemd?

AJWM Condemned. (533 comments)

As the legendary Henry Spencer said, "Those who do not understand Unix are condemned to reinvent it, poorly."

Clearly the folks behind systemd do not understand Unix.

about 4 months ago

Ask Slashdot: Practical Alternatives To Systemd?

AJWM Re:Accept, don't fight, systemd (533 comments)

If there are things you don't like about systemd, you should write up coherent bug reports or feature requests,

That doesn't work if it's the whole design philosophy you don't like. Whatever happened to the Unix philosophy that tools should do one thing, and do it well, and be easy to integrate with (not assimilate, borg-like) other components?

Me, I'll keep SysV init. How often do you need to reboot a unix or linux box anyway?

about 4 months ago

Programming Language Diversity On the Rise

AJWM Re:A good sign (177 comments)

+1 nostalgia if I had the mod points. Heck, there was a time (about 3 decades back) when I was being paid to teach APL (or APL, as properly rendered).

Mind, the bit-arrays used in ElasticSearch filtering strike me as a very APL-like idiom. You never know when something you learned back when will prove useful again.

about 4 months ago



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