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Brooklyn Father And Son Launch Homemade Spacecraft

mnemonic_ Yes, they can. (243 comments)

It's space flight, or orbital flight. Different from atmospheric flight. But this is a stupid semantic debate I'll avoid.

more than 3 years ago

How To Behave At a Software Company?

mnemonic_ What terrible advice (842 comments)

At a hiring event at a hotel, I overheard a hiring manager of a large defense contractor in the restroom ranting about the college kids he was interviewing. Paraphrased, "They're all technically competent as engineers! But there are no social skills, no fit!" He was yelling. He went on to rave about a female engineering interviewee, who was "confident without being arrogant, funny, and personable" and how she would be a perfect hire, because she was sociable. I can guarantee the "work, not talk" line wouldn't have worked on this guy, at least.

Also, have you ever read The Art of War? It's not about avoidance and being a lone wolf. It is about facing conflict head-on, adapting to the environment, while stressing unconventional approaches (attacks). Eating lunch alone, cold shouldering coworkers, being an oblivious worker drone - this is exactly what Art of War warns against.

more than 4 years ago

I've originated Q Wikipedia articles, where Q =

mnemonic_ It's an encyclopedia (256 comments)

Wikipedia isn't an indiscriminate repository of information. It is finite, not only because of finite resources (note how often they ask for donations? storage and bandwidth aren't free.) but also because each additional article requires more editor attention for copyediting and preventing abuse. Every article about something no one cares about draws editor attention away from articles that matter. I eventually stopped contributing to Wikipedia (beyond minor fixes) because of qualms with the editing process, but the greater discretion in deleting articles is something I welcome. It was absurd how many Slashdot-related articles there were when 99% of the first world's adult population has never heard of it. Granted, we still have garbage like Dalek, and by most measures, it's still the encyclopedia Slashdot built.

more than 4 years ago

Correcting Poor Typing Technique?

mnemonic_ Uh, no (425 comments)

Learning french doesn't mean you forget english. I've been a full time Dvorak user for six years, except for public terminals at university and public library computers. They all use qwerty, and I type on them nearly as well as in Dvorak (maybe 70 wpm versus 80-90 wpm on Dvorak). I have lost some speed in qwerty, but the comfort and lower chance of RSI is well worth using a non-standard layout. Reaching 70 wpm in qwerty is hardly crippled typing.

more than 4 years ago

FOSS CAD and 3D Modeling Software?

mnemonic_ Or before even that... (413 comments)

They're worrying about CAD when they should be worrying about calculations and broad, system-level design. Remember, the first moon missions took place without the use of CAD. Detail designing the parts is a relatively small part of aerospace engineering. A better approach would be to prove their engineering legitimacy by analysis, then impress IBM/Dassault enough to donate a CATIA license to them. Give the rough launch vehicle design, the mission orbit design, the reentry vehicle type, and detailed quantified justifications and tradeoff studies for everything. It should be heavy with physics, and the calculations should be airtight. Expect a 500+ page technical report for this scale of project at this preliminary stage. Any explanatory sketches can be done by hand or any illustration program. You only need CAD when you're (1) ready to machine parts or (2) ready for detailed computational analysis. These guys are jumping the gun.

CAD isn't just about coming up with the part geometry by the way. Modern CAD/PLM involves massive amounts of metadata about materials, dimensions/tolerances (all locked in proprietary file formats), and keeping track of the relationships between parts, sub-assemblies and assemblies. You don't want to manually copy & paste 300 fasteners each time you recalculate stresses on a rocket nozzle, do you? It also automates many tedious design efforts. Want to figure out how to snake twenty miles of wiring, hydraulics and other tubing through a rocket with a hundred thousand parts? Oh also, each type of cable/tubing has a different minimum bend radius because of material stresses. Arc it too tightly and it cracks open during the launch vibrations, after having fatigued due to ambient thermal variations. And these are just a couple mechanical aspects of such a sprawling project that CAD must handle. You could "draw" the parts of just about any modern machine (fighter jet, car, bicycle) with an old copy of Maya used for the CGI in Jurassic Park. It'd be useless for analysis though because of the low numerical precision, and impossible for engineering because they have the most primitive handling of parametric modeling, and crude ability to work with multi-component (thousands) geometry.

Any teenager can come up with some gee-whiz 3d animation (that Mars lander animation from years ago was done by one). Could any teenager get funding for a mission to the moon? Work on your numbers first, then worry about software, you IT geeks you.

more than 4 years ago

FOSS CAD and 3D Modeling Software?

mnemonic_ lol (413 comments)

Is this a joke? Your team page shows you have at most four engineers, who are mostly IT geeks, not experts in propulsion, aerospace structures or astrodynamics, with the possible exception of Dr Snyder. You have a fricken artist before having a real engineering team, or anything solid to promote. You guys make Armadillo Aerospace look like Lockheed Martin. At least SpaceX etc. while lacking other things, started with something (usually money), you guys don't have anything. Quit wasting your time.

more than 4 years ago

House Outlaws Obama's NASA Intervention

mnemonic_ There are fundamental differences (209 comments)

Chem rockets can't achieve the efficiency of jet engines because they carry their own fuel and oxidizer. Jets only carry fuel and thus need to propel less weight. Rockets also must generate enough thrust to support the entire vehicle weight. Jets normally fly at thrust-to-weight ratios below one, by having wings that rest on the surrounding medium (air, lift). Rockets must also propel their payloads under these conditions to ~330,000 ft. Commercial airliners reach cruising altitude at 35-40,000 ft. The climb gulps fuel, but the following cruise sips it; rockets are climbing the entire time. This is all scraped from undergrad propulsion, but I think it's right.

One solution is to combine propulsion methods, to use airbreathing propulsion for atmospheric flight and rockets beyond. This could be either a combined-cycle engine (turbine with a rocket in the spindle), or something like SpaceShipOne/White Knight, where a jet-powered platform brings a rocket-ship to altitude. Chemical rocket costs aren't just limited by rocket makers trying to maximize profits on limited launches. They're inherently less efficient than airbreathing propulsion, but aren't limited by the atmosphere.

more than 4 years ago

Bing Cashback Can Cost You Money

mnemonic_ soo... (333 comments)

Did anyone else notice the story submitter's alias links to a sex toy shopping site?

more than 4 years ago

PulseAudio Creator Responds To Critics

mnemonic_ Benevolent dictators (815 comments)

It's only accepted as long as infighting between developers continues to waste energy on all sides. A war of attrition that's characterized open source for so long that no one knows any better (1984, war is peace). A "benevolent dictator" should roundup the sound guys and stop their fucking around. Mark Shuttleworth shaped Ubuntu up to be the ONLY decent desktop linux distro, Guido van Rossum made Python a uniquely usable and efficient programming language (ditching backwards compatibility with the 3.0 release), and Steve Jobs carried Apple out of the gutter. So many open source projects flounder without strong (and sometimes arbitrary appearing) direction.

more than 4 years ago

India's First Stealth Fighter To Fly In 4 Months

mnemonic_ Misguided (611 comments)

Fantastic investment when the extent of enemy combatants' airpower are RPG's that can't hit anything above a few hundred feet, and much of your population has no running water.

more than 4 years ago

Dell Says Re-Imaging HDs a Burden If Word Banned

mnemonic_ Huh? (376 comments)


more than 4 years ago

What Questions Should a Prospective Employee Ask?

mnemonic_ I've used these... (569 comments)

How many meetings do you have?
This always gets a laugh, valuable when potential engineering hires usually seem quite dry. Meetings usually waste time, and their answer will give you a better idea of how much real work you can actually achieve.

What's your relationship with academia?
This question is good if you're interested in more researchy-work, or have grad school on the horizon (or in your past). Companies that associate with universities tend to do more serious research. If you plan to attend grad school, working for a company connected with academia will get you a letter of recommendation appearing much stronger to the professors who handle PhD admissions.

Is there a dresscode?
You'll probably know the answer to this beforehand, but some companies aren't so clear. The aeronautical engineering field is generally business-casual, but I've interviewed at two aero companies where anything goes. For some people, this can be a significant workplace comfort issue and indicative of overall work environment.

How selective are you with tuition reimbursement?
Most engineering companies will compensate you for taking courses at a nearby university (or online). Some companies only pay for courses related to your work, others will let you take courses in anything. It can be a nice perk to finally take that astronomy or life drawing course you couldn't squeeze in during undergrad.

more than 4 years ago

20 Years of MS Word and Why It Should Die a Swift Death

mnemonic_ Irrational bias? (843 comments)

Well, I work in a team engineering environment where everyone already HAS Word and KNOWS Word, and no report is a solo effort. I can't force everyone to spend weeks learning my cool pet app/language and let other projects fall by the wayside. These people aren't programmers. I don't know, is lost productivity due to cost of switching rational enough for you? Not everyone is a contract programmer working from home, which is something a lot of Slashdotters seem to miss.

Oh, and I've run linux for seven years (Mandrake, Slackware, Gentoo, then Ubuntu), most recently for six months as my only OS - until I switched to Mac. Before OOo (which I use at home without issue), I used StarOffice in high school to write my chemistry reports. The lack of understanding from FOSS advocates, and their presumptuous attitudes impedes their attempts at inroads more than the quality of their software. New solutions MUST play nicely (more like FLAWLESSLY) with existing solutions if there's to be ANY change, unless the existing solution is obviously flawed to users. Most of the time, it isn't. Corporate inertia. It sucks, but that's the real world.

more than 4 years ago

Preview the Office 2007 Ribbon-Like UI Floated For OpenOffice.Org

mnemonic_ Context-sensitive UI ftw (617 comments)

Yeah, the Ribbon is much more efficient. The key was recognizing that context-sensitive menus reduce user workload in finding what he needs. There are two approaches to displaying functions in an application to a user:

  1. Assume nothing, and display all functions in lots of menus. Very simple and straightforward, but user must dig through a lot of chaff to find what he needs. Repetitive access to frequently used items becomes tedious, but everyone gets a static interface.
  2. Assume some things. It's known from common sense and usability studies that most users working on Item X probably would use Tools Y and Z. Likewise, he probably wouldn't benefit from Tools A and B, so those should be tucked away. It's strange to have a dynamic interface like this, and takes some training, but when done well it streamlines function access.

#1, the static interface, is traditional. #2, the dynamic interface, is the Ribbon, but also the Mac OS top task menu, and the toolbox in the Gimp. We're less used to context-sensitive menus in word processors, but when we realize that these have become fullblown page layout and formatting packages, it makes more sense. People aren't just typing letters in word processors, but also formatting newsletters, compiling engineering reports and writing technical PhD theses (with equations, charts, tables of contents, special characters out the wazoo...). These have blossomed into powerful apps for combining and organizing text, mathematical, graphics and tabular information, far more than the typewriters they originally replaced. With that current usage, a dumb interface with forests of menus or tabs doesn't make sense and totally slows down the project. The application should, and can, take care of the user's needs a bit more, and with the Ribbon in Office 2007 it's worked splendidly.

more than 4 years ago

20 Years of MS Word and Why It Should Die a Swift Death

mnemonic_ Word isn't just for printing (843 comments)

I keep Word because I still need to format documents. Notepad isn't appropriate for a 100+ page document with a table of contents, figures, equations, tables etc. Is there a more convenient way of formatting a complex technical report that doesn't involve some kind of word processor? It doesn't matter if it's being printed, organizing such a body of work and conveying the information clearly requires more than a text editor.

more than 4 years ago

The Open Source Design Conundrum

mnemonic_ I agree (322 comments)

Ubuntu, Apple products and the Python programming language have all stood out with their exceptional usability because of their "benevolent dictators." When everything's decided by committee (even loose ones like in FOSS), every drastic but beneficial change will be pecked down by the naysayers. Something like Python 3's intentional backwards incompatibility, done for the sake of a vastly cleaner language syntax would never had made it without Guido's spearheading of the effort.

more than 5 years ago

Steorn's "Free Energy" Jury Comes Back To Bite Them

mnemonic_ Are they asking for money? (213 comments)

Are they actually asking for money now? I've just skimmed their site, and the closest I've found are that they let you contact them about "accessing" the technology. There's an Investor Relations page, with numbers that are four years old and that doesn't seem to be linked from the main site any more. There doesn't seem to be any clear way to join the project as an investor though. If they're trying to scam people, it's a modest effort.

My guess is that the company fervently believes they've worked out free energy, but only out of some hazy measurements that they haven't yet nailed down. They're seeing the mirage of perpetual motion in some device they can barely analyze because their equipment sucks and because they lack experience. They'll improve their instrumentation eventually, work out the kinks, and quantify that it's not outputting more energy than that input, and move on.

"Any sufficiently advanced technology is indistinguishable from magic." Until, that is, it's understood. They don't understand what they've done and haven't been able to quantify anything, they think it's something impossible (read: magic), but eventually the truth will emerge and they'll drop it.

more than 5 years ago

Open Source FPS Game Alien Arena 2009 Released

mnemonic_ Doesn't work (142 comments)

I just tried running it on Ubuntu 9.04 and it segfaults on sound initialization. Meanwhile, my sound works perfectly well in anything else I try. It's stupid problems like this why linux isn't ready for the desktop. Don't give me excuses about searching for howto's or configuring it right. If I run a mainstream distro, on extremely common hardware (Dell Inspiron laptop), everything should be fucking flawless.

more than 5 years ago



Bad Math Skills Lead to Bad Mortgages

mnemonic_ mnemonic_ writes  |  more than 4 years ago

James Cho writes "Not all subprime borrowers are alike. While all having poor credit histories, the Economist reports that those who failed a simple arithmetic test defaulted at rate much higher than that of test-passing borrowers. The results come from a working paper by the Federal Reserve Bank of Atlanta: 'Foreclosure starts are approximately two-thirds lower in the group with the highest measured level of numerical ability compared with the group with the lowest measured level,' quantifying the problem of public innumeracy."
Link to Original Source

Accurate Replica Hiroshima Bomb Built by Trucker

mnemonic_ mnemonic_ writes  |  more than 5 years ago

James Cho writes "Through a decade of painstaking reverse engineering, trucker John Coster-Mullen built the first accurate replica of the Hiroshima bomb. His work yielded a new history of the first nukes, 'Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man,' with historian Robert Norris saying, 'Nothing else in the Manhattan Project literature comes close.' Philip Morrison, one of the physicists who helped invent the bomb deemed it, 'a remarkable job.'"
Link to Original Source

Why isn't encryption the norm?

mnemonic_ mnemonic_ writes  |  more than 5 years ago

James Cho writes "Today, I encrypted my entire hard disk with TrueCrypt. The effect was transparent. After entering the password on boot, the system ran exactly as before, but with the security of every bit set to disk encrypted. Vista Ultimate and OS X both include user-activated robust data encryption without any performance hit (though not full disk). The technology is here, vetted by academia, industry and government, and there's certainly reasonable cause — but no one uses it. Does anyone see why operating systems shouldn't encrypt all data by default?"

mnemonic_ mnemonic_ writes  |  more than 7 years ago

j (164550) writes "For decades, FORTRAN has been the hallmark of academic computing, with object-oriented principles taking a backseat to slick matrix handling and sheer speed. Meanwhile, C++ was stigmatized for its bulkiness and verbose syntax of matrices and vectors. The Blitz++ library for C++ is rapidly encroaching on that. Nearly matching FORTRAN in performance, Blitz++ offers an intuitive matrix handling syntax (with an elegant cout response) essential for efficient mathematical expressions. With Sun's Fortress several years away, will Blitz++ be adequate to introduce robust OOP to numerical computing? And is that even needed?"


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