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Submission + - Bad Math Skills Lead to Bad Mortgages ( 2

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."

Comment What terrible advice (Score 1) 842

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.

Comment It's an encyclopedia (Score 0) 256

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.

Comment Uh, no (Score 1) 425

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.

Comment Or before even that... (Score 5, Insightful) 413

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.

Comment lol (Score 5, Insightful) 413

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.

Comment There are fundamental differences (Score 2, Informative) 209

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.


The World's First Osmotic Power Plant 262

ElectricSteve writes "Her Royal Highness Crown Princess Mette-Marit of Norway officially opened the world's first osmotic power plant prototype on November 24. The prototype has a limited production capacity and will be used primarily for testing and data validation, leading to the construction of a commercial power plant in a few years time. Statkraft claims that the technology has the global potential to generate clean, renewable energy equivalent to China's total electricity consumption in 2002 or half of the EU's total power production" What's osmotic power? Wikipedia to the rescue!

Submission + - SPAM: AKC Dog Breeds

bontil80 writes: "In AKC dog breeds, you can learn more about dog food and the nursery from the dog.Looking for AKC DOG BREEDS? Here's AKC DOGS BREEDS information for you!
Want to learn about AKC dog breeds? Loads of AKC dogs breeds tips and tricks, all FREE here."

Link to Original Source

Comment Benevolent dictators (Score 1) 815

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.

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