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Comment: Re:Wildly premature question (Score 1) 81

by Bruce Perens (#48620117) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

If we look at jet aircraft, wear depends on the airframe and the engines, and the airframe seems to be the number of pressurize/depressurize cycles as well as the running hours. Engines get swapped out routinely but when the airframe has enough stress it's time to retire the aircraft lest it suffer catastrophic failure. Rockets are different in scale (much greater stresses) but we can expect the failure points due to age to be those two, with the addition of one main rocket-specific failure point: cryogenic tanks.

How long each will be reliable can be established using ground-based environmental testing. Nobody has the numbers for Falcon 9R yet.

Weight vs. reusable life will become a design decision in rocket design.

Comment: except they're almost #1 in highway deaths (Score 1) 525

by SuperBanana (#48498777) Attached to: Montana Lawmakers Propose 85 Mph Speed Limit On Interstates

"People actually drove reasonably well and there weren't any major issues with it. "

Except for leading the nation in deaths per highway mile...yeah, I suppose?

Funny how the only person I know to be killed in a traffic collision was, in fact, killed by a drunk driver in Montana.

People don't drive "reasonably well" - ever. People have poorly maintained vehicles, especially in a by-and-large poor state like Montana with very little vehicle inspection. People stare at their cell phones, don't keep their windshields clean, don't use sunglasses, drink, spend too much time fiddling with the radio, get distracted by passengers. Our nation devotes virtually zero resources to any enforcement of traffic laws except speeding. Unless Montana starts doing roadside spot vehicle inspections when they are caught breaking some other law...

Guess who picks up the tab for the millions of dollars in medical care when Joe Cowboy slams his pickup truck into a family of four because he was doing 90mph and his bald tires couldn't stop him in time? The federal government, aka You and Me.

Comment: Re:Wooden bikes are cool (Score 1) 71

by SuperBanana (#48414931) Attached to: Collin Graver and his Wooden Bicycle (Video)

"They're much like normal biles otherwise and I presume exactly as comfortable."

Comfort comes almost entirely from the tire size and pressure relative to rider weight and road conditions. The frame is largely irrelevant, at least for anything made in the last few decades by any half-competent company.

"Getting the bearings and power transmission were apparently the harddest bits."

Getting alignment on these items is the hardest bit. Bicycles require an incredible degree of proper alignment of a couple of key components in order for things to work right, mostly shifting, but also handling-wise.

Comment: Irrelevant (Score 1) 71

by SuperBanana (#48414919) Attached to: Collin Graver and his Wooden Bicycle (Video)

"I'd guess that yet another disadvantage of a wooden bicycle, at least when sharing the road with motor vehicles, is that it's impossible to trigger a green traffic signal without enough metal surface to disturb the flux in the induction loop beneath the approach to the intersection."

1)Inductive loop sensors are much better than they used to be, and many can detect aluminum bike frames, metal in the wheels (almost all spokes are metal - carbon fiber spokes are very rare; many rims are still aluminum), or the metal in the drivetrain (chain, cables, derailleurs.)

2)A large percentage of bicycle frames are made from carbon fiber; even many wheels these days. No different from wood.

3)Many traffic lights now use camera-bases systems. They're cheaper and easier to set up/maintain, and can quantify the number of vehicles for better decisions regarding prioritization, etc. I think some can detect emergency vehicles, provide traffic statistics, and record video if there's a crash.

Some, but not all states, allow cyclists to go through a light if it doesn't change for them after X minutes. Idaho allows cyclists to treat red lights as stop signs, a law groups are trying to get passed here.

Comment: Boneshakers did not have pneumatic tires (Score 1) 71

by SuperBanana (#48414839) Attached to: Collin Graver and his Wooden Bicycle (Video)

They were boneshakers because they didn't have pneumatic tires. This is not true of a modern bicycle, and we also have far more understanding of mechanical systems and materials, including wood, now.

It is a widely perpetuated myth, mostly by bicycle frame makers who are attempting to get you to spend gobs of money on special designs, frame materials, etc that are "vertically stiff and horizontally compliant" (this phrase is now such marketing cliche it's mocked a lot)...that road bicycle suspension happens in the frame. It doesn't/shouldn't. It happens almost entirely in the tire/tube; when you go over a bump, the rest of the tube+tire stretches slightly to absorb the impact, and then contracts back. Some suspension also happens in the wheel; a wheel is quite strong in part because the spokes and rim both have some give to them.

Just as with cars, the most effective suspension is the one that has the least unsprung weight. So for example, high performance cars often have suspension and brake components made out of high-strength-for-weight materials, but in general, car manufacturers try to keep the weight of the suspension down.

On a bicycle with a properly sized and inflated tire for the rider's weight and road conditions, there is very little unsprung mass

Comment: Why are you a corporate shill? (Score 5, Interesting) 111

by SuperBanana (#48412401) Attached to: Interviews: Ask Malcolm Gladwell a Question

http://shameproject.com/report...

Why did you, after college, attend the National Journalism Center, a corporate-funded program created to counter the mediaâ(TM)s alleged âoeanti-business biasâ?

Why, as someone who is half-Jamaican, have you repeatedly associated yourself (and apparently continue to do so) with the white supremacist organization EPPC, which fights activists for economic justice?

Why did you write for American Spectator, which churned out anti-Clinton conspiracy theories?

Why did you recycle tobacco industry propaganda and quote lobbyists for Washington Post articles you "wrote"? Why did Phillip Morris consider you, according to their internal documents, to be a "friend" who could be counted on for pro-tobacco-industry stories?

Why did you clearly promote drugs for treating ADHD in kids, in which you heavily quoted researchers who were paid heavily by the pharma industry?

Why did you cite a pharma-industry cited study and defend the industry when it was attacked for high drug costs?

Why did you blame the victims in the Enron collapse, defending executives who committed gross fraud?

Comment: Wikipedia the vector (Score 1) 61

by Bruce Perens (#48386659) Attached to: Researchers Forecast the Spread of Diseases Using Wikipedia

Like others I found the headline confusing. I read it as "Researchers are predicting the use of Wikipedia as a vector for the spread of disease". This may mean that:

  • Disinformation and ignorance are diseases.
  • Memes and computer viruses are diseases.
  • Wilipedia contains information that leads to depression.
  • Instructions on Wikipedia lead to substance abuse.
  • This is getting entertaining, fill in your own reason here.

Comment: Re:Not a good week... (Score 1) 445

by Bruce Perens (#48298059) Attached to: Virgin Galactic SpaceShipTwo Crashes

One of the definitions I found was:

One who makes great sacrifices or suffers much in order to further a belief, cause, or principle.

I am sure that fits. While SpaceShip II is mainly intended for a non-exploration purpose, the program has resulted in some significant advances in rocketry and White Knight II has significant non-tourism use. These pilots have been involved in other space efforts, I remember the one who was injured from the Rotary Rocket test flights. There are lots of safer ways for these folks to make as much money as a test pilot is paid. They do what they do to advance our progress in aeronautics and space.

Statistics are no substitute for judgement. -- Henry Clay

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