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Comment Supervision (Score 1) 349

For students younger than College age, supervision is needed in the classroom. What was told here was that the Teacher had trouble monitoring the students, and so avoided the problem by removing the tool. For teachers without the proper background or without the proper tools, this would be a good approach.

What the tablets (or netbooks or whatever) need is to have the teacher able to monitor what programs are running, and shut down any non-educational ones. That vital piece of the puzzle was apparently lacking. Letting the kids just use the tablets without any monitoring is going to be an epic FAIL. The problem came from up the IT food chain in the School District.

This problem is not really a new one. When I was in school, it was common for a student to slip a comic book into his/her textbook to read during study time. A simple blank piece of paper also works, if you have a pencil or pen. (Remember passing notes in Jr High and High School. It hasn't stopped, just gone more high tech.) My Wife, a remedial reading teacher in a Jr. High school, confiscates several cell phones each semester for texting in class. The phones are turned into the office, and the parents have to come and pick them up.

Tablets are really just one more distraction if they are not locked down.

Comment Re:Models are always right! (Score 1) 760

Models are really just guesses. To have any validity, they need to be checked against what really happens. If they don't give results to match, then they need to be reworked. Often with different assumptions.

It is possible to map any possible set of points to a graph with any of a nearly unliimited set of models. Having the model then successfully predict a future set of points is what makes the model valid. Predicting the past is easy. Predicting the future is hard.

Many of the climate models are so complex that the modelers are not even aware of what the all the model variables are. Some of the models are only correct after various adjustments are made on every new data point. In physics, this is referred to as having a 'fudge factor' in the model. A fudge factor is the different between what the model predicted and what you observed. when added to the model output, it corrects the model to account for the new data point. Most models require a new fudge factor for each new data point.

It's not new, it has been with us in science for as long as we have had science. It only really means that the modelers don't understand the process that is being modeled. That means that only a fool would believe the outputs.

I hope that you aren't basing your national policy on the output of these models. The good results are usually not any better than the bad ones.

But, you shouldn't worry a whole lot, according to the models run in the 1970's we all froze to death ten years ago anyway.

Comment Re:Phew... (Score 1) 760

No, the overall Earth ecosystem doesn't care about per capita. It only matters what the totals are. The totals are that China burns more stuff than the US does. Also, the US grows more carbon containing stuff than China does. (That is not included in the graphs, trees and such.) This is a function of arable land area. Population doesn't even enter into it. That means we put less in the air, and take more out of it. Of stuff we don't seem to want in it ( CO2), that is.

Canada also burns less than China does, and also grows more trees and bushes and other plant matter than china does too.

Why can't supposed Geeks understand simple addition and multiplication? I realize he is preaching his religion, but it's not coming across as anything but brain dead.

Comment Re:Phew... (Score 1) 760

The infrastructure isn't there yet. But, with electrified roads, and a Google type autodriver, you could just get in and let the car drive you to your destination. I would want to schedule 3 or 4 stops along the way.

there are several ways to electrify the roads. The simplest would be to have a rail trolley like the trains in France use. Then, just run a power line along one lane of any freeway. You car will draw power directly from the power line. You will literally NEVER have to stop for gas. A system like this could be installed within 3 years, coast to coast and north to south. The biggest problem is getting the cars to have the trolley system. That would take the addition of a lift. but, trains in europe have been using the same system for over 30 years now. It works.

Perhaps less costly would be to electrify the rail lines, and just load your car onto a flatbed, then either stay in the car, or get in a passenger car on the train.

Oh, you are wrong about the cost of catanary lines for railroad tracks. There are already poles and signal lines up all along the tracks. It's really just the cost of stringing the wire. It would take less than a year and probably less than $10 Billion to make the switch. More expensive would be retrofitting the locomotives to fully electric. However, for the true high speed rail they are using in Europe and Asia, our tracks aren't built for the speed. We use trains that go less than half the speed. (70 verses 150 MPH). Whole rail lines would have to have all the curves relaid. Different slopes, different bracing, perhaps different spacing, different radii, there is a need for a lot of engineering there.

Compared to the cost of changing the track, the cost of overhead lines is minor. We have of course changed out the tracks and relaid the curves before. A couple of times in fact. it takes about a decade to do it. We went from light gage rails to heavy gage rails, then from narrow track to wide track. For the track, this is just one more change.

The real problem is to convince the railroads to do it. We can't right now. Federal rules are designed to promote trucks and discourage trains for cargo. That is union driven. The Teamsters are already mad as wet hens about the cost advantages of rail over road travel as it is. If the railroads thought they could recapture a bunch of the passenger travel from the Airlines, and if they could take back more of the cargo traffic from the truckers, they would do it. As I said, it would take around a decade, and it would be a pay as you go type system.

The Government would have to support an increase in the power grid to add the additional load. 3 or 4 large reactors should do it.

So, how about it. If you could go from Las Vegas to Virgina in half the time that it will take you to drive, and for half the cost, would you?

Flying would still take half the time, but that is less and less important as the distances are lessened.

And, you are correct, this will be much more successful in higher density areas. Along the east coast from Virginia to Maine is a no brainer. Same with California from San Diego up to Sacramento, and over to Las Vegas.

Perhaps a New York to Albany to Chicago by way of Pittsburgh and Detroit line.

Those will probably be the initial big money routes.

Similar routes from LA to Las Vegas and from Phoenix to Tucson, then pushing west to LA have been proposed for a couple of decades now. Nevada almost paid for a LA to LV line twenty years ago, but backed out at the last minute. They wanted to make it easier to gamble in Vegas than in the California Indian casinos.

So far, no group has been willing or able to put up a couple of Billion to do it. Arizona almost did the Phoenix-Tucson tie five years ago, but the budget crash happened and killed that. A half hour between downtown to downtown would mean that a lot more people would be able to live along that corridor and work at either end. It would pay for itself over a ten year period. But, not this decade. There are now other priorities.

See, it can be done. It isn't a question of technology, or even of economics. It's much more a question of politics. These networks aren't built a nation at a time, it's more a question of a line at a time.

It's been that way for over 30 years now. 30 years and waiting.

Comment Re:Phew... (Score 1) 760

Hamsters work, if you have enough of them, and if you are not addicted to speed.

Imagine the look of a 10,000 Hamster roadster! That would be impressive!

I wonder how many miles per ton of seed you would get? You could probably fertilize the entire neighborhood before you even got all the way down the block!

On a completely different topic, there is a group that is trying to get permission to build a Thorium powered sports car. It gets supposedly around 150,000 KMPKG (Km/Kg of fuel), and only needs a modest particle accelerator. They are projecting a cost of around $5,000.00 for the 200 KW power plant when it reaches mass production. Just add an electric vehicle. The thing is not much more radioactive than a standard university Nuclear Howitzer (a source of Alpha particles for experiments, not a weapon). It is steel encased, with a lead shield. Weighs around a Ton, only a little heavier than an old V8 twin four barrel muscle car engine (think Mach II Mustang). It should be able to go into immediate production, right after they get NRC approval. There is supposed to be almost no radioactive by-products. So write your Congresscritter.

See more about this at any of the following:


Or, you could just let Google do the walking.

I love the line that "The car will wear out before you need to refuel." I think Yugo tried that a some years ago, but it didn't work out too well for them.

I have also seen a wind powered car that can go over 70 MPH in a good stiff breeze. It was on the road in Michigan in the mid 1970's. It was cool. It looked like a three wheeled glider with no wings or elevators, and a big eight foot tall arch where the wings should be. It did best in a crosswind, which that part of Michigan always has, so your dreams can still live.

See, all of these are possible. Except for a people carrying Hamstermobile, all of these are being worked on, or have already been done. And, I have seen concept hamtermobiles, though they could only carry a couple of ounces of cargo/riders, as they only used a single hamster.

The Hamster concept still needs scaling up.

Comment Re:Phew... (Score 1) 760

Cost is still too expensive, though the cost has come down an order of magnitude or two.

But yes, getting the pollution off planet is a good long term idea. After all, on the Moon, there is no ecology to damage. There is even less in orbit than on the moon. We don't want to hurt the rocks feelings, now, do we?

One problem though, the fuel supply for this orbital solar thing is only good for around 5 Billion Years. It may already be hitting it's Hubbart peak. After all, according to Astronomers and other Respected Scientists, it's already half used up. There also seems to be an idea of Solar Warming floating around out there.

Any ideas? Shouldn't we already be looking for another star?

Comment Re:To all candidates (Score 1) 343

This 'DeRegulation you so fear and hate is not what you think it is.

The Government didn't stop regulating. They haven't done that in the Financial markets since 1912. The Government didn't stop regulating the Mining industry. They haven't done that since the early 1920's. The Government didn't stop regulating telecoms or any of the other monopolies.

What they did was to let the fox guard the henhouse. The Fed is after all a private company run by a few large banks. It should be no surprise that they act to support those same large banks. The fed is in fact overseen by people from the same large banks.

Much the same is true of the Stock Markets and the equities exchanges. Who are the Regulators? Bernie Madoff was one once. Doesn't that give you a nice warm feeling? He was watching out for you. Just like Ken Lay once did.

The same is true for most monopolies. When Microsoft was convicted of antitrust violation under Bush (the trial was started under Clinton), Microsoft was allowed to write the settlement they wanted. Before you start to go and Bushbash, remember that six years earlier, the same thing happened under Clinton. Both sides are equally at fault.

Who regulates the railroads? Railroad executives who are on temporary loan to the Government. Who regulates the Medical field? The Doctors Union (AMA) supplies people to the Federal Government.

The problem isn't that there is no regulation, or that it has been somehow disabled. The problem is in how it is being implemented. Sorry, but we have had that problem all the way back to the Grant Administration in 1868.

The Stock Market was regulated when it crashed in 1929. It just wasn't regulated well. The Banks were regulated in 1930 when so many failed, they just weren't regulated well. The Electrical Energy Markets weren't unregulated when the Enron manipulation caused the collapse of the energy availability market in 2001, it just wasn't regulated well. The Housing Mortgage Market wasn't unregulated when it collapsed in 2009, it just wasn't regulated well.

Some of these were the result of action by the regulated organizations, some were the result of large players who knew what the results would be, and some were the results of acts of Congress. Some were "D. All of the above."

Do you see a pattern here? Perhaps we should consider having someone other than industry insiders or Congressional profit takers doing the regulating?

And so it goes. The Fox really is the Hen house guard. And no one is held responsible.

Comment Re:To all candidates (Score 1) 343

I think you have Ron Paul confused with Barak Obama. They have different views.

Ron Paul is the one who thinks that half of the government should be abolished. No, not the defense department, though he would like to pare it down to the size that Eisenhower wanted, basically just the sargents and officers (Who will spend most peacetime playing insipid games while the sargents really run the Army like they always do), with a small core of soldiers for the officers to command for the Army, and keep the Navy, though about a third of the ships could be just placed in storage. Air Force about half way between Army and Navy. Marines, they are part of the Navy.

No, it's the rest of the government he would like to be rid of, The IRS, the Welfare, Education and such like departments. Anything that doesn't pay for itself. He believes that around half of what the Federal Government does is unconstitutional. That half is what he really wants to eliminate. He would have no trouble achieving or surpassing President Obama's goal of eliminating 1.4 Trillion Dollars from the Federal Governments budget. He would probably eliminate twice that.

If any of that is wise is another question entirely. So also is the question of if he could actually DO any of it.

Barak Obama on the other hand wants to expand entitlements (Money the Government promises to give people and corporations). He is the candidate that believes that when you are in debt, the way to get out of debt is to spend more money. After all, -1-1=2 right? To be honest, he probably learned this sort of math in the Senate. That is how Senators seem to think. It doesn't appear to matter which Party they officially belong to.

Also, to continue to be honest, Barak Obama like George Bush (2) before him has most of his problems stemming from action outside the US, or from acts of Congress. Like Bush, he is more a victim of the Pelosi-Reid congress than anything else. Presidents get blamed for everything, and they appear to have a great deal of power, but reality is that they mostly respond to external events and are charged with implementing whatever the House of Representatives and the Senate can sort of agree on saying should be done.

Sorry, that is the job description according to the US Constitution. The President can push and cajole and plead and bargain, but can't just spend arbitrarily or pass their own laws or programs. A US President is much more a COO than a CEO. A President is more a manager than an autocrat. That doesn't mean that some of them don't act like autocrats or even Kings (Andrew Jackson comes to mind). Both the best and worst Presidents appear to have been in office in the 1800s, no matter what Glen Beck says.

No, Barak Obama's presidency is really just about what the Pelosi-Reid Congress said to do. It takes a little over a year for the changes in congress to take effect. So, we will see the effects of the Bohner-Reid Congress by next summer. But, no President in the US ever has a really free hand. The press of course ignores this, and the majority of citizens don't even know it. After all, how many do you think have ever read the US Constitution? Of those, how many do you think understood it? If we take the comments here on Slashdot as typical for the population as a whole, the answers to both questions fall somewhere between very few and none.

However, for the purposes of the actual header for this fine but pointless debate, Barak Obama, definitely. He is running. On the other side, Mitt Romney, as the assumed future victor for the Republicans. The others all seem to be self destructing. Except Perry, who having already self destructing is now trying to destroy everyone else.

Perhaps Hermann Cain too. He sounds interesting. Maybe not credible, but interesting. Sort of like Joe Biden that way, though not wrong as often.

Any of the others who are declared would be nice.

Maybe even Sarah Palin (Yeah, I know she's not even running, but, Obama campaigned mostly against George Bush when HE (Bush) wasn't even running. After that, why should we be surprised that Barak Obama doesn't look like he knows what he is doing? He didn't even know who he was running against three years ago. We saw what we where getting before we ever got it, so we got what we wanted. Don't let any Democrat complain about Obama. They saw what they were getting long before they got it. That was what they wanted. There have been no surprises in this Presidency!) Yes, Sarah would be interesting and educational. Most Slashdotters only know about her from late night comics and journalists who only listen to and quote late night comics. (That is more of them than you might think. a surprising number of them only really listen to people at their cocktail parties and some even just make stuff up.) Slashdot readers might be surprised to find what she really says. It's not what we are told. Kind of like those who 20 years ago thought they knew all about then Vice President Dan Quayle and his statements, but what they thought were Quayle quotes were really Jay Leno quotes. Often Politics is the art of misleading the stupid. (Yes, that would be you!)

From my perspective, her husband, Mr. Palin, would be even better. An Iditarod winner, a major salmon fisherman and a world class snowmobiler. That's better than ANY politician to me.

Comment Re:Microelectronics? Nanodiamond? (Score 1) 80

No, read the Article. They used methane to grow the diamond films, sort of like the gaseous diffusion they use to grow semiconductor layers in Silicone.

That deposits the Carbon one atom at a time. It's not micro, Nano, Pico or even Exo. It's much smaller than that. We don't have prefix's for that level of smallness. It's Atomic.

Comment I Remember ... (Score 2) 80

I remember reading about this kind of thing in the mid 1990's. Scientific American reported on it. At the time, they were making diamond films on ceramic substrates. the diamond was grown by creating a carbon atom plasma and shooting it at the substrate. Shock plasma deposition of the carbon. It wasn't very efficient. They hadn't worked out too well how to mask and etch the films, so they were using electron beams tp cut into the diamond, then adding the dopant. That limited the size of the device produced. The device was around the diameter of a pencil eraser. The researchers (in Japan, if I remember correctly) were predicting commercial development in as little as five years. Well, I never saw anything come of it.

I was looking forward to that coming out too. I am an electrical engineer, and have worked for a long time with plans for building facilities and power lines and so forth. The device made in Japan was a single SCR (silicon controlled rectifier) that would work just fine at 600 Volts, and a little over 200 Amps. It operated at a temperature of a little over 600 degrees C, but still, an SCR can be used for many power applications. That single SCR was controlling a around 120KW. For big AC to DC power lines, we use SCR banks where each of the SCRs operate at about 24 Volts relative to the next SCR in the stack. This for stacks that go up to 750 KV. The stacks are paralleled to get the current that actually goes out over the line. One such line goes from Washing State to LA, and carries close to 10% of the total power used by LA. for what I was doing at the time. These diamond SCRs would have made a great speed control motor starter. At 480 VAC, we could have made the controller with six SCR's, three fuses, and a disconnect switch, plus a small PLC board. The control station would be bigger than the controller. Typical controllers for this type of application on say a 100 HP motor are around 7 feet tall, 4 to 10 feet wide and 3 to 6 feet deep. reducing this to 2 Feet wide, 3 feet high and 1 foot deep would free up a lot of space. This, if purchasable, would have given me a lot more freedom in placement. If I could reduce the size of the controller, the process people would have loved to use the extra space. I could have used that to justify spending up to $100,000.00 more for the device, in some cases.

We could really use such a device in industry. There are a ton of uses that I could think of off the top of my head. Used as an ultracapacitor controller, it would enable a single capacitor, the size of a couple of C cell batteries to store more power than a car battery. A large electronically controlled circuit breaker, with custom controls, and a quick action would also help to save a lot of equipment and lives.

There were a couple of real problems with it, though. First, it's flammable. The actual electronics would need to be isolated from any contact with oxygen. Encapsulation would do that. Real Graphene computer chips, which I would expect to see before this matures, would also be flammable. But, there are more options for protecting those, because of the relatively lower temperatures.

Also, the Diamond SCR's operated at temperatures higher than some common conductors can withstand, and well above the temperature at which Diamond burns. There would have to be special connectors, and cooling systems. That heat, even if from a small eraser sized element needs to go somewhere. Ultimately out into the environment.

Second, it's apparently not an easily commercialized process or material. I am seeing more reports of Diamond film growth, and also of graphene film growth and production. That is a good thing. Graphene seems to be moving towards fabrication faster than diamond. I would like to see both happening. I have also seen recently, that very low impedance conductors have recently been made from carbon nanotubes. While not room temperature superconductors, if they have lower conductivity than copper, I would really like to be able to specify them. Cost would be a factor there. But, cost can be accounted for, if they deliver a performance maintenance advantage I run in to this all the time with choices of copper verses Aluminum for building wire. If they can be used as superconductors at near to or higher temperatures than the liquid nitrogen superconductors, then they would be able to fill a need also.

If these things can all come together, we will see more changes in the next 10 years than in the last 10, or even 20 years. I hope we do.

Forget Di-Lithium, we have Diamond Semi. The real thing!

Comment Re:Why is this notable? (Score 1) 351

"electricity is nearly useless for lifting spacecraft in all models except Heinlein's imaginary mass drivers."

Actually, it is really easy. The higher the acceleration, the shorter the distance required. The energy is easily supplied by solar power. Add a capacitor bank, and a much lower peak power is needed. Your figures are for peak load. If the launch is not a continuous operation, then average power is sufficient.

For a 100 KG payload, at 20 G, (200 M/S^2) that would take 12 Seconds (2380/200) to reach the velocity you quoted. That's at 20,000 Kg M/S^2, or roughly 20 Kilowatts. double it for inefficiencies, and you get a 40 KW power source needed to deliver a 100 KG payload to earth every 12 seconds. At 25% efficiency, in the 1 KW per square meter sunlight on the Moon, that's 160 square meters of solar cells to launch using "imaginary mass drivers" that are already installed on Navy ships. Granted, the barrels for this system would be long. (200 X 12^2 /2 = 14,400 Meters), but if you increase the acceleration, you decrease the track length. The payload could withstand easily an acceleration of 10X that. People, not so much. It's long for a gun barrel, but not bad at all for a rail line. It's not like the thing has to be pointed straight up.

It would be a waste to ship fuel from Earth You are right there. But, that won't be done, except in very small loads in the first few years.

Rail guns are being developed right now that would do for shipping insensitive materials from the Moon to the Earth. They are being installed in Navy ships today. Power is just a question of finding available surface area and having a source of silicon or carbon to use in solar cell manufacture. The Moon has lots of silicon. You also need aluminum, Also very common on the Moon.

Surface area is not a problem either. Most of the Moon is unused. So is a lot of orbital space. As the Hitchhikers Guide says, "Space is really BIG!" Lasers and microwaves are being developed to move power from place to place, and are now to the stage that the Military is seriously considering satellite based power purchases. It's expensive, but they think it will be cheaper than the alternative. It currently costs more than $100.00 per gallon to get fuel to the front lines in Afghanistan. That makes generator power very costly.

But, I don't believe that Helium mining will ever be anything more than a byproduct of other minimg and manufacturing on the Moon. In that, I agree with you.

Comment Re:Why is this notable? (Score 1) 351

Gobi Desert. Already been done. It is called Mongolia.

For a similar desert scene, a little closer to home, you might want to consider Phoenix. Has the same extreme temperatures, the same arid conditions though winters are milder. Summer is hotter than in the Gobi. Phoenix is easy to find. Just go to the Grand Canyon, then head south until you get to a really big city.

A Moon base would need to have orbital farms to be really sustainable. Big rotating cans with windows would be all that's needed there. The two week day and night cycle on the Moon would be a real killer for plants. But, people could deal with it. Life there would be much like living in the Mall. Lots of Kids do that anyway. For a few months at a time it's OK. Probably wouldn't want to leave people on the Moon for long er than 6 months before roatating them to earth normal gravity anyway..We don't want their bones to soften.

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