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Comment: BLDC Motors (Score 1) 75

by metaforest (#49508057) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Are extremely efficient for their mass and volume. The key issue they must overcome is cooling. If the motor is in the liquid stream, (and this is a likely assumption) cooling is damn near free. As for the power supply, I am fairly sure that the reduced mass, complexity of the pump, plumbing and associated benefits with reducing the volume of the pump system that must survive extreme temperature and pressure, more than make up for the battery mass.

Those that doubt the tech will scale up to larger designs don't really understand how flexible BLDC motor configurations can be. Comparing a custom engineered BLDC motor application with a stock industrial motor, even a stock BLDC, is simply a waste of effort. Modern BLDC hobby motors can easily produce 16 HP/kg with air cooling for intervals similar to what these turbine pumps need to do at efficiencies up to about 95%. I'm sure they do much better when liquid cooled. The battery tech is not quite as good at scaling yet, so some kind of fuel cell might be needed to produce the required electricity, but I could see this approach working for pump designs that scale to what Falcon 1 can do now with gas powered turbines.

TL;DR: Reducing the pump to an integrated Impeller/motor result in enough reduction in mass and complexity that using primary batteries to power the pumps is a net gain in lift capacity compared to a traditional gas turbine pump design.

Comment: Re:Innovation vs. Commodity (Score 1) 392

by metaforest (#49238605) Attached to: Does USB Type C Herald the End of Apple's Proprietary Connectors?

The other key for VHS adoption: it was a consortium standard, not a Sony exclusive. All the consortium partners cross-liscensed their relevant patents. That led to a diversity of VHS compliant and compatible systems that trumped Sony's exclusive offering. The only real technical failure of Beta was the 1 hour recording limit.

Comment: Hey... maybe you just need a math class (Score 1) 144

by metaforest (#49212409) Attached to: Go R, Young Man

How about after teaching Algebra, but before heading off into Trig and Calculus spend a quarter or two on Discrete Math. Right there in one fell swoop is the foundation of all computer science in one fairly easy to grasp branch of mathematics. Tie that in with a bit of PASCAL or Python and there is your wade into programming without forcing students into a CIS track. For budding programmers, that class would tie their foundation together, and with others it just gives them some insight into how a computer or even just a calculator really works.

Orienting the study around languages only works with people who already have some idea of how to program.

Comment: Re:Consumers win (Score 1) 210

by metaforest (#49156239) Attached to: Lenovo Saying Goodbye To Bloatware

If you weren't so cheap, you could have been buying computers not covered in crap for years. Apple has never sold computers with crap like that on it.

The problem is, you want to pay $100 for a $2000 device and ignore the consequences.

Lenovo hasn't actually done this yet, and when they do, they won't be the first.

[emphasis added]
This is simply not true.
Apple included 3rd party crapware on their computers just as often as the PC OEMs did until the second coming of Jobs.

Comment: Re:Honestly (Score 1) 187

by metaforest (#49004085) Attached to: The Poem That Passed the Turing Test

This goes back to some ideas Neal Stephenson was scratching at in Anathema.

Humans know that the symbols their minds operate on MEAN something. Our minds operate on the meaning of symbols not the symbols themselves.

No machine she have ever built has anything close to such a capacity. In Stephenson's parlance such machines are only capable of parsing syntax to operate on it, and transform it into more syntax.

We have a long way to go before machines can understand their instructions, and thus operate on meaning, rather than syntax.

Comment: I know a lot of female geeks... (Score 1) 779

by metaforest (#48977391) Attached to: WA Bill Takes Aim at Boys' Dominance In Computer Classes

They are focused on biochemistry, biology, medicine, audio engineering, geology, architecture, marine biology, genetic engineering, truck mechanics, electrical technicians, etc. I have only met a few that were hip to CS in any real sense. Those few were either UI designers/developers (yes they wrote code), or Psychology majors with an interest in UX (didn't write code for development, but did write code for processing their study data).

Stop the pigeon-holing! Many disciplines encourage their practitioners to learn coding, indirectly! HOWEVER, most of the specific personages I reference indirectly above were coders because their disciplinary goals required that they learn to write code on their own, NOT because their discipline requires it, but because their projects indirectly require it! Having a strong coding background myself I was in a position to offer useful advice on where they could refine their skills to achieve their disciplinary goals with code. It really had very little to do with pure CIS... It had to do with getting a pie-eating-contest off their plate so they could move on to the rest of their research!

Code development is not an end. It is a means to accomplish a disciplinary goal that cannot be solved by any other method, and all of the academic and professional women I have met dealing with that particular challenge grok that. They don't love computers, but they know what such machines can do for them, and they are more than willing to roll up their sleeves to learn it, and keep their hands dirty in it, only so long as that effort is required to satisfy that portion of their larger goal.


In K-12 teach Discrete Math, Data Structures, Algorithms and call it good. If you must get feed back, teach them a core language like ANSI C. But let it go after that. Make it a required section of every math class, scale it to fit the level expected for that student. By the end of k-12 every student should know what an integer and a float is, what a pointer is, what arrays and strings are, what control statements are, and why they are important for computer processing. This should be true even if they never want to see a line of code again. Put it where it belongs. Programming is applied math. Treat it as such. Don't bury women in a discipline that does not interest them. Teach them how they can apply Discrete Math and automatic computation in their own path.

Coda: Women generally won't spend 20 years studying one species of dragonfly -- guys have, and do similar things all the time. That is a guy thing.

Women, if they focus down on something like fruit fly larva, it is generally for a greater purpose that tends to broaden their efforts not narrow them. That is a key difference between guys and gals. Guys are content, for a lot of bad, or ill-defined reasons, to narrow down to a laser fine focus on shit that most women just can't be bothered with. It is not that women can't do it, or won't do it! I think it is more that they recognize it is usually self-destructive and self-limiting. I think the feminine approach is healthier, for a lot of reasons.


Comment: C/PM and a VOTRAX (Score 1) 79

by metaforest (#48955553) Attached to: How Blind Programmers Write Code

First time I saw blind programmer was a professional C/PM App developer back around 1982. He used a minimalist text editor and a Votrax speech speech synth as the print device. I was in high school at the time and said programmer was the father of a fellow hacker in my Pod of computer, theater, and gamer nerds. Seeing (and hearing) this kids father program in C and Fortran was fascinating.

You want to accommodate blind developers? Give them CLI access to every element of the system, with consistent shortcuts and high quality voice//auditory feedback for navigation in screen-format editors.

The only reason this particular developer had a CRT is because it was an integrated part of the serial terminal he used to communicate with the host system.

Comment: Re:just put a motor on the elevator itself (Score 1) 248

by metaforest (#48940701) Attached to: Engineers Develop 'Ultrarope' For World's Highest Elevator

The current approach uses a counterweight that balances out the empty mass of the elevator cabin. This drastically reduces the load the motor must carry, and thus the size of the motor. If you want to put the prime mover on the cabin you are going to have to solve a lot of scaling problems that the current approach avoids.

Comment: Sounds not heard anymore (Score 1) 790

by metaforest (#48799399) Attached to: Ask Slashdot: Sounds We Don't Hear Any More?

The weird ticking of a tube driven TV warming up, or cooling off after it is turned off.

The odd creepy voice and tones of WWV. (yes I know it still exists, but who listens to it to set their clocks anymore?)

High speed paper tape punch.

Keypunch terminal.

Electromechanical adding machine.... chek.chek.chek.chek....chek.chek.-kathunk-whirrrr.
Idle sound of an IBM Selectric.

Speech warning module from a Nissan 200SX. It used a tiny stack of records on a common shaft, each with it's own double sided stylus assembly. "Dink! The Door is Ajar...Dink! The Door is Ajar...Dink! The Door is Ajar..." (No it is NOT.. it is a DOOR!)

The rather tuneful sound of a Macintosh 400K floppy disk drive due its CLV motor drive.

Dolby-C calibration tones on the leader of prosumer tape editions of albums such as Dark Side of the Moon.

The odd fluttery sound of 16mm film audio when the playback loop collapses.

Credit Card Slip Imprinter.

CPU bus cycles of a 1MHz 6502 leaking through the front end of an AM radio.

CB radio bleed-through on TV channel 4 or 5 audio.

The eery duck squawk of CB-SSB transmissions.

Air Raid siren tests in south bay area every few weeks. Sometimes the system would glitch and there would just be a 1/2 second "Blurp!" that floated over the crickets, and frogs in middle of the night.

The heavy mechanical thunk of a VHF channel selector from a Tube TV.

The howls of frustration when the power goes out in a large game arcade.
The mixed electronic and electromechanical cacophony of power coming back on in a large game arcade after a power outage.

An electromechanical jukebox changing records.

A mechanical cigarette machine dispensing a pack.

Comment: Re:Scum (Score 1) 190

by metaforest (#48798255) Attached to: Tesla vs. Car Dealers: the Lobbyist Went Down To Georgia

Mobile service techs are exactly how Tesla does it. I've met a couple of them through one of my clients. They used to work for high end auto dealers such as Bentley or Audi working in the shop. Now they drive a Tesla-badged service truck and perform on-site service almost exclusively. Both of the guys I spoke with said they love working on Teslas because even stuff that is traditionally a PITA (like swapping out major suspension components) can be done in the field with nothing more than a portable jack and a pneumatic wrench.

Comment: Re:Guinness (Score 1) 130

by metaforest (#48606505) Attached to: No More Foamy Beer, Thanks To Magnets

There was a Pub in Boston that I had the pleasure of visiting in 1986 that had their Guinness flown in from Dublin. I was quite fond of Guinness at the time. The combination of it being served at room temp, and being astonishingly fresh had me thinking that I'd been drinking stale beer back home in CA. I didn't get to experience that again until I visited England in 2005 during a layover on my way to Russia. I gave up drinking Guinness after that. Here on the west coast it just doesn't taste right.

Comment: Re:Just in time. (Score 1) 219

by metaforest (#48605965) Attached to: Seagate Bulks Up With New 8 Terabyte 'Archive' Hard Drive

Seizegate -- from the late 80's and early 90's round of SCSI and PIDE drives that suffered from early spindle bearing failure and sticktion problems.
Sleazegate -- ever since... for various sleazy tricks like selling 3 year warranty drives into channels where the case manufacturer would only warranty the drives for 1 year. Bad firmware... poor customer service on warrantee issues, PR games...

  I simply will not buy prefabbed external drives anymore. I buy an empty case and stick a 'who has the best quality record this year aside from Seagate' drive in the case.

The absent ones are always at fault.