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Comment: Turbines Past and Powerful (Score 1) 338

by DynaSoar (#33925568) Attached to: The Rise and Fall of America's Jet-Powered Car

In 1967 Parnelli Jones was on the verge of winning the Indianapolis 500 in Andy Granitelli's Pratt & Whitney gas turbine racer, when a transmission part broke too close to the end of the race to recover from. So impressive was his performance that rather than risk having the race taken over by non-piston machine, they re-regulated turbines requiring them to have no more than 14 square inches of air intake, effectively crippling their performance. Parnelli commented at the time that he thought they could adapt and win anyway.

The facts of history and of mechanics remain. Turbines are one of those things suppressed, whether purposefully or not, by a status quo threatened.

Comment: Let Me Guess (Score 1) 264

by DynaSoar (#33913722) Attached to: How To Deflect an Asteroid With Today's Technology

Rusty's answer is "gravity tractor", right? Same as last time this story ran. That one included the fact that he wanted to build and presumably sell said widgets. Since he hasn't, that's hardly today's technology.

Today's technology would be something already tested. Say, the cable and reel used on the shuttle's tethered power generation experiment. Land a large reel of cable, anchor the end, and let centripedal force throw the reel out. After it's tens of kilometers out, the center of gravity will have shifted and the rotation will have slowed. Figure the best direction to throw the rock, wait for the rotation to get it close to that, and blow explosive bolts on the anchor. It doesn't take much change in trajectory to turn a hit to a miss if it's done early enough.
   

Comment: Scanners (Score 2, Insightful) 66

by DynaSoar (#33888532) Attached to: Study Shows Brain Responds More To Close Friends

In the absence of specifics, I can only wonder whether they used a flat bed or a hand held.

How they get from brain activity they know virtually nothing about to the abstraction of social value is beyond me. It's beyond them too, but they don't let that slow them down.

The brain responds to familiarity. The more prior associations that had been formed due to a particular stimulus, the more those associations are re-activated when presented with the same stimulus. The brain also responds to unfamiliarity, but in a different manner. The experimental design to test for these is called 'go/no-go'. AFAICT they just did a memory test here.
 

Comment: Arms to Armas (Score 1) 123

by DynaSoar (#33885366) Attached to: Milky Way Is Square(ish), According To New Map

"Astronomers know of a number of other galaxies with straight arms, such as the pinwheel galaxy M101. So ours probably looks something like this."

Astronomers know of spirals and barred spirals. TFA says SOME of the arms are straight. There aren't many 'both' spirals. Most likely the different shapes of arms represent this galaxy's original arms and those of the galaxy it absorbed, in which our sun originated. Compared to the problems of evolving differently shaped arms, this is the simpler explanation, and testable by observation.

Comment: 1 oh 1 (Score 1) 366

by DynaSoar (#33850158) Attached to: Simple Virus For Teaching?

"I am looking for a virus with which I can infect the lab computers (only connected to local network, no outside network connection) that would be easy for the students to remove by hand. Can the Slashdot community point me in any directions?"

Yes. Teach them some useful Computer 101 stuff instead of wasting time on stuff that makes the computers useless. If you must cover the subject let them read http://en.wikipedia.org/wiki/Robert_Tappan_Morris Before you infect any machines, you should too.

Comment: How 'Green'? (Score 3, Interesting) 239

by DynaSoar (#33792552) Attached to: West Virginia Is Geothermically Active

Will they be scraping even more mountains off the planet to get to it? Will they fill the remaining creek beds up with the effluvia from getting to it? Will they keep even more public roads under a permanent state of "repair" and detour to disguise the fact that they're simply ruining more tax funded roadway with heavy machinery? Will they drive residents out of even more entire towns due to blasting damages and constant noise from heavy machinery? Are they going to do anything with the energy rather than find cheaper ways to dig coal? WV has two industries, coal and railroad. If they replaced coal money with energy money the railroads would die. They won't let that happen. They've been fighting off a 3/4 MV high tension line for years, you think they're going to allow an energy exporting industry to pop up, string wire for multi MV lines and sell electricity to its neighbors now that they're got them hooked on WV coal? I lived there are loved it. But I realized the state is owned by stockholders for whom green is considered a place to dig. Even of they took advantage of a chance to do something good, they wouldn't do it right -- they'd do it cheaply to maximize profits and the population would suffer the effects. WV *was* green. It's owners don't give a shit about green.
   

Comment: The Case For Internet Licenses (Score 2, Insightful) 196

by DynaSoar (#33792260) Attached to: Comcast Warns Customers Suspected of Bot Infection

"Of course, if you have multiple machines running behind a router or modem then you're going to have a difficult time pinning down which machine might have the infection."

If you call turning off your machines and running them one at a time to check each machine's response "difficult", then you can damn well pay the neighbor kid to come over and do it for you, just like you paid him to come over and get your Internet Explorer brand computers surfing on the infotube highway in the first place. While he's there, have him take out that "MOE - DEM" thingy. Those blinking lights are just slowing things down.

Comment: Re:Get a kitchen timer (Score 3, Informative) 178

by DynaSoar (#33791708) Attached to: Best Mobile Computing Options For People With RSI?

Get a kitchen timer and a laptop and a tablet. Set the timer for 30 minutes and bang away at the desk. When the bell rings, move the laptop to the top of the filing cabinet for 30 minutes. When the bell rings again, take it to the couch. Next time the bell rings, move to the other side of the couch and use the tablet. Then take a meeting and lunch. Start back at the desk again after lunch. Get up now and then. Take a walk. Evenings and weekends, pull some weeds play WII Fit for a half hour, then billiards and table tennis or whatever. Get different motions going on. RSI isn't about excess motion. It's about repetitive motion. Different motions help make it go away.

No, different motions help prevent it. Once inflamed, repetitive motion of any sort is more likely to aggravate it. If there's permanent damage, any repetitive motions will exacerbate it to the extent that motion uses the damaged parts, and trying to force use on other parts taking up the slack can irritate them. Changing positions between equally unsuitable orientations will in turn irritate the damaged part and stress the as yet undamaged. The position that uses the injured parts least and the uninjured maximally and proportional to their abilities will be least likely to cause strain, pain and more injury. Using that position with the mechanism requiring least effort is optimal.

Comment: Extreme Adaptation (Score 1) 178

by DynaSoar (#33791664) Attached to: Best Mobile Computing Options For People With RSI?

I've got one very damaged wrist and one embedded titanium bar, both victim of several accidents and far too much surgery for body parts to endure without accumulating more damage in the repair process. I can't write with a pencil for more than two minutes due to the tendons being as much scar tissue as anything else.

But my thumbs work fine by themselves. Thus I use trackballs like the Logitech M570. Once learned and used at highest response speed, I can, for instance, play an entire game of solitaire in less than 100 seconds. The rest of the hand rests on the device with very little movement required to trigger the buttons, thus the least effort is required to support them. I tried many different methods before finding this. It's the least tiring, in fact not at all, nor do I end up hurting after. Since my arm rests on the table, I don't even use the braces anymore.

Comment: !Spacecraft (Score 2, Informative) 243

by DynaSoar (#33779724) Attached to: Brooklyn Father And Son Launch Homemade Spacecraft

1. It is a balloon. Not even the people who fly these for a living call them spacecraft. Says WikiP: "A spacecraft is a craft or machine designed for spaceflight." This thing popped when it rose above too much atmosphere. It was not designed for space. It was still in the stratosphere when it failed according to design.

2. The Karman line is the generally accepted edge of space at 100 km (62.5 mi). This is where an aircraft would have to fly so fast to get lift from the thin air that it would achieve orbital velocity in the attempt and so wings would be superfluous. The US has awarded astronaut wings to pilots flying above 50 miles. This doesn't change the objective criteria of the Karman line.

3. The CSXT GoFast achieved space altitude (72 miles) on May 17 2004 and is the only unmanned civilian craft to do so to date. It was designed for a flight profile carrying it into space and so was a spacecraft. As was SpaceShip One, the only civilian manned spacecraft to date.

4. Reaction Research Society hit 50 miles in 1996. Hunstville L5 passed this 19 mile mark, but was ballooned launched and so not entirely spacecraft.

5. No amateur spacecraft made from off the shelf or home made components has achieved even a 50K ft altitude according to Tripoli records. With Tripoli and the National Association of Rocketry's recent facing down ATFE over the definition of 'explosives', the FAA et al. is redefining amateur rocketry to include power up to 200,000 lb-ft sec and a concominant (and easily achieved with this power) 93 mile altitude. Most motors in this range are "experimental" ie. home made, but there are a few commercially available motors that can be staged and/or clustered for this power, the 152mm dia + 96" Loki Research P motor at 80kN-sec each being the largest you can currently put on your credit card. 11 of these will put you just under the FAA's proposed limit. 12, and you have to apply to NASA's office of space transportation for a permit. Expect an amateur spacecraft to make the flight, because now it's a matter of qualifying for the license and buying the parts.
 

Comment: Two Dimensions, One Viewpoint (Score 1) 69

by DynaSoar (#33770234) Attached to: How Will the Constellations Change In 50K Years?

"From The Earth" is rather prosaic when you compare it to 3 dimensions. Look at any constellation from the side. The distances are usually much greater than the apparent angular separation as seen from Earth. It makes it quite obvious that 'constellation' is as synonymous with 'illusion' as it is with anything else. But from the side you can see that some groupings hold, such as the majority of Taurus. Most of it is an open cluster, so of course things won't change much in 50K years, the members are moving together through the sky on parallel paths. And it's the cluster that's moving more than the local stars, so the one "moving" in these pictures is really just getting passed by.

Earth's (Sol's) location as it moves affects these, but not as much as its position over a much longer time scale, like 250M years. In that time you can see the milky way wash up and down the sky a few times, like a huge wave. Seen from outside the galaxy, it's obvious why. The sun and the local group of stars in traveling around the galactic center, but the orbit swings back and forth through the galactic plane two and a half times as it oscillates it way around the center. We'll lose almost all the constellations at the peaks because we'll be outside the populated arms.

All this makes 50K years from one viewpoint rather humdrum. It also suggests an answer to one of the SETI questions, why aren't they here. If technical and traveling civilizations exist in the numbers supposed, and they wanted to go to other stars, they would probably want to go to those they know would be in the neighborhood for some time. Among the last they would consider visiting would be a small group of tiny stars, none greater than 8.5 absolute magnitude, that used to belong to another galaxy ripped to shreds by this one and on a trajectory taking them out of the plane of the majority of stars. For half the next 50 million years they'll be more isolated than the present 90% of the way out from the center position. And on each pass-through more and more of these interlopers will be captured by the galactic arms, so who can say where they'll end up, IF they slow down and hang around. They could get thrown out of their own grouping entirely and end up hovering around in the galactic halo too far from anyplace to be accessible (relatively). So why go to those, when there's thousands times more stable members of the galactic arms? All that disruption makes it unlikely there's any life on those tiny galactic fast-walkers anyway.

But if we did happen to get thrown out of the local group's obit and outside the galaxy, no more constellations then. Instead we'd have the entire galaxy all on one side, in one hemisphere of the sky. With a view like that, who needs constellations?
 

Comment: AN Answer, not THE Answer (Score 1) 176

by DynaSoar (#33738490) Attached to: Study Finds the Perfect Ratio of Attractiveness

This is a very common topic in social psychology experiments. Many that are published fall prey to an error of calling the example selected most to be 'attractive'. It's more correct to say that the most common answer is the most common opinion of attractiveness. In the press to prove their point, they ignore the fact that a less common answer is also an opinion of attractiveness, just to fewer people. Just because more guys like the hard, bony ones with corners so sharp they bruise you and threaten to poke holes in the water bed doesn't mean some don't consider the softer, more squeezable ones to be attractive.

And while you're getting your 'fat chick' jokes ready to throw, keep in mind that the less likely a guy is to get a girl at all, the more likely he is to adopt an attractiveness standard in line with the majority (so he can lie as much as possible) but to an even greater degree (so he can better lies than the other guys do do). He might as well claim that's his preference since he's not likely to get any sort, and will take advantage of any chance to toss his artificial preference out for others to see, expecting them to take his preference as a history. Yes, there's an awful lot of this attractiveness research done, and only some of it tends to reach erroneous conclusions.
 

Comment: Re:It's been done before (Score 1) 65

by DynaSoar (#33733104) Attached to: Destroy Entire Websites With <em>Asteroids</em> Bookmarklet

Perhaps not as creatively, but back in the *last* century there was an browser addon that allowed you to throw tomatoes, or blast an offending webpage with different weapons [rifle or shotgun IIRC].

You could even screen cap the results and post the mutilated page as well. It soon lost its novelty and waddled off into the dustbin of Idle history. I'm sure this one will as well.

I just wish I could remember who published it, or what it was called.

feh, spoiled brats. Got it all handed to you.

In the century before that one, we didn't even have a browser add on. All we had was View Source and a text editor. We had to edit the page's code by hand. And then, we couldn't shoot anything at the web page -- all we could do was throw rocks at our monitors. And THEN we had to edit the page's code from MEMORY. It was tough, but we were better for it.

I tell ya, you kids got it easy. Browser add ons and asteroids and hemeroids and enemas and NURSE! NURSE, WHERE'S MY SNACK? AND WHERE'S MY CAPS LOCK? oh there it is. Was I saying something?

Comment: The Really Bad Astronomer (Score 1) 295

by DynaSoar (#33730336) Attached to: Fifty Meter Asteroid Might Hit Earth In 2098

The last time I caught Plait living up to his marketing gimmick, it was also about asteroids. He fell into the common trap of starting with the descriptive statistic (an asteroid of X size has hit every Y years on average) and assuming the predictive (last one hit Z years ago so the next one is due in Y - Z years). He should know better. These objects are independent. One has nothing to do with another (unless the happen to bump each other). If one hits today, the next may hit in a billion years or tomorrow. While you *can* make an average out of X events in Y years, it tells you nothing that can be used for anything.

This time it has to do with reporting science vs. reporting news. This NEW system has found one object that its calculations suggest something about. How accurate and precise is it? That can be estimated but can't be proven without replication and comparison with other instruments. And apparently if it has been, they haven't arrived at the same conclusion. This rock does not appear in the SENTRY data as displayed on NASA's NEO Program impact risk tables, not even as an only recently observed object, as of 27 Sept. It's not among the objects removed from the list either, so the teams contributing to SENTRY haven't seen it or the data associated in order to check the validity of the instrument, much less the claims. Things are not as PANStarrs says, or they're making claims without corroboration.

There *is* an object with a 5.5% chance of impact in 2095 -- 2010 RF12. But it's a whopping 7 meters diameter. And having been observed for a whole 3 days, that probability is extremely likely to fall drastically. That one object kicks the total cumulative impact probability up over 2% for the next century, but only for now. The cumulative will probably fall right back to the 1.5% before this object appeared.

But as for 2010 ST3, nowhere to be found. Real astronomers should know better than to announce something from a new instrument as though it's a conclusion. At best they have a data set for the SENTRY people to check over and verify their measurements. Other real astronomers should call out the ones who make such claims. Bad astronomers, masquerading as bad science writers, obviously would rather pretend to refute some aspects of the implications without bothering to talk about things like validity, replication and responsible reporting.

Comment: Except, No (Score 4, Interesting) 92

by DynaSoar (#33719794) Attached to: Rewiring a Damaged Brain

The brain already does this itself. It's called neural plasticity. If they brain can do it, it will. If it can't, sticking wires into it and applying shocks and other intrusions and insults is not going to make it happen. Not properly anyway.

TFA is about neural jumper cables that can focus on only the signals they want, bypass damage and send the signal to another location. Fine idea except you kill the target quickly. But it specifically states "artificially". That makes the stuff about guiding axonal growth complete bullshit.

Neural connection is guided by glial cells, which are half the brain. If a region is damaged, both kinds of cells are damaged -- there's nothing to guide the growth of neural cells which are also damaged anyway. If you stimulate growth without the guiding mechanism, the cells form a tangle called a neuroma. The best outcome would be no result. Such neuromas caused by severed nerves, such as in amputations ('stump neuromas') are one of the causes of phantom limb pain. Neuromas in the cortex may not cause pain, but if they produce any result other than none, it'll be wrong and potentially interfering with function in the undamaged areas. Plus, stimulating growth where it can't happen properly is an excellent way to stimulate excessive, unguided, pathological growth -- tumors.

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