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Comment: Re:intuitively I would think steam would be better (Score 1) 217 217

I mean, exactly what gas were you imagining a nuclear reactor running a gas turbine with?

The gas would be air from the atmosphere. I suppose a closed loop with helium or carbon dioxide might be used but I suspect an open loop system would be much less prone to failure.

As you say it is possible to boil water with any heat source so long as you have a proper heat exchanger. The problem with a high temperature reactor, such as a molten salt reactor, is that to use it to boil steam a number of heat exchangers would be needed to lower the temperature to something that could be used to boil water. It's possible but not likely something someone would want on a ship as it would be quite large. Boiling water with a 400C reactor core temperature is nearly trivial. Doing so with a 800C reactor core temperature is nearly suicidal.

I should not have implied it impossible o boil water from a high temperature reactor, merely impractical on a ship at sea.

Comment: Re:intuitively I would think steam would be better (Score 2) 217 217

What happens if one of the capacitor banks fails or the electro magnet blows up right during the discharge process? Nothing good I would bet.

What happens on a steam catapult if a pipe bursts during launch? Nothing good I would bet.

Mechanical systems fail, there's no avoiding that. What they have with EMALS is a system that they've determined to have a lower probability to fail.

I'll answer some of your questions and hopefully point out how an electric system is superior to a steam system. First is that the energy for launch is not stored in capacitors. There are four flywheels on board which are spun up slowly and can drive an alternator to produce the electric pulse required. I assume that there is redundancy here so that if any one flywheel fails in a critical moment the others can compensate.

With EMALS there is a computer system that can monitor the force and acceleration of the catapult. A failure of a single magnet along the line would likely be detected and the others used with increased power to compensate. This might mean a bumpy ride for the pilot but not a loss of the airframe. A similar failure with steam could likely mean loss of the airframe, and possibly the pilot.

There is also a very practical need to move away from steam catapults. The Navy wants to use the catapults to launch aircraft of a much wider weight range, from UAVs, to figher jets, to small cargo planes. Steam catapults lack the ability to handle such a wide range of loads. The Navy is also experimenting with alternatives to steam propulsion for the ship. Now they are still using a solid fuel nuclear reactor to boil water but that is not likely to remain the case. Higher temperature liquid fuel reactors are too hot to boil water but are very efficient at driving gas turbines. The Navy will still need electricity for things like lights, heat, radar, communications, and so on so the electric generation capability will always remain. If the steam generators can be removed then that means more room for fuel, crew, munitions, and redundant electric generation.

Comment: Great! More noise on ISM frequencies! (Score 1) 59 59

As someone with a reputation of knowing how electronics work among friends and relatives I am often asked to fix issues of interference on wireless devices. What is often the case is the baby monitor, Wi-FI, cordless phone, and microwave oven all operate on the same frequency. Now we get someone that wants to power his toys by transmitting noise in that band.

The article claims that the test subjects saw no drop in their Wi-Fi access from the use of this device. I don't doubt the report, I just expect that this was not a real world test by having other common wireless devices operating at the same time.

I wonder if the "greenies" will latch onto this. Given the unrealistic claims of energy sources and power distribution systems from these people I expect someone will read this report and expect to see all the power lines in the world disappear and be replaced with antennas.

Comment: Whatever, it's been done (Score 1) 81 81

I recall seeing film on TV of a US Army project that had a device very similar to this. It had a man standing on top of a hovering platform with lift provided by fans. I don't recall exactly when this demonstration was performed but judging by the quality of the film, uniform of the "pilot", and other clues it was likely 1950s or 1960s. Perhaps there is a "first" here that I missed.

Comment: Re:not the real question (Score 2) 200 200

You can't charge someone with having killed "someone" unless you name that someone.

Also, would not that someone have to be proven to be dead? The FBI claims that Roberts caused a plane to move in a manner that resulted from his actions. If someone can show the movement was in fact because of pilot action, or from wind, then there is no crime. Right?

Comment: Re:Save the buggy whip makers! (Score 1) 615 615

People are not horses. Horses cannot own property, they are property. Saying that horses haven't found a new purpose in the days of the automobile is like saying we have not found new uses for a sextant in the days of GPS. A horse is a tool. People might be considered a tool but they are also the customer.

People like to deal with people, not machines. Unless there is some legal change that allows for machines to have authorities like that of arrest we will need people. This might mean an economy where a large portion of the population is employed to watch machines work all day but then how it that fundamentally different from now? A co-worker once told me that 90% of IT is watching a progress bar.

People are not going to obsolete themselves.

Also along with that thought of people wanting to deal with people is that I believe we are a very long way away from people allowing machines to watch their children. We will need teachers, nurses, nannies, and so forth. In the future we'll probably see class sizes shrink from 30 to 50 that we see now to where it's more like 3 to 5. I did customer support for a while and people will go out of their way to avoid talking to a machine. I can offer an automated system to process their payments but I can't make them. No company in their right mind is going to do away with the people that process money because that means potentially alienating a large number of customers.

Horses don't buy stuff. Robots don't buy stuff. People buy stuff.

So long as people can buy stuff there will be people willing to work so that they can buy stuff. The few unwilling to work to buy stuff will be arrested and detained by those that do.

Comment: Re:Save the buggy whip makers! (Score 1) 615 615

We've had two millennia of technological advancement which have made much of the labor that people do obsolete. Even though at one time a large portion of the population was employed rowing boats we don't seem to have an unemployment problem on the scale of jobs lost to the internal combustion engine.

What will these former truck drivers do? I don't know but we've found work to make up for all kinds of jobs lost in the past. What did the buggy whip makers do? What of the people that spun ropes by hand? What of the butchers, bakers, and candlestick makers? Do we still send people to get bled so that leeches aren't put out of work?

I don't know what these people are going to do but it appears we always find something for them. I'm not going to hold up technology just because the people that make buggy whips and shovel up horse shit might have to find a different job.

If unemployment gets real bad then perhaps we can legalize prostitution. That should keep people employed. If these people are so ugly and unskilled that they can't find work fucking then maybe they can find work in politics.

Comment: Re:"what other things do you usually carry around" (Score 1) 278 278

I'd like to carry my Colt M1911 but as one of my customers is a factory that hires convicts I must leave it at home.

On my keyring is keys for my truck, house, and gun cases, also a combination light and bottle opener, Swisstech Utilikey, wireless fob for truck.

Commonly in my pockets are cell phone, iPod touch, wallet, handkerchief, medicine bottle, pocket knife (don't tell the prison guards), and maybe change for parking meters and vending machines. If I'm wearing my carpenter pants I often shove a water bottle in one of the larger pockets.

I will often be found with a messenger bag filled with stuff. Swisstech tool, pens, pencils, Post-it notepad, chargers for phone and iPod, band-aids, Tylenol, Zyrtec, antacids, and any documents or books I need for the day. I almost always carry food, mostly just some granola bars and a bottle of water and/or Coke, sometimes a full lunch. If I need a computer that day I'll put in a Macbook Pro, USB mouse, and charger. That bag does get large and heavy.

Comment: Save the buggy whip makers! (Score 1) 615 615

I see this every time a new technology that comes along that could replace human laborers, technology means millions will lose their jobs. What always happens is that these people all seem to be capable of finding other work. The work I do in computers did not exist before computers existed. Before the electronic computers existed there was a job description called "computer". Had I lived in an earlier age I'd probably be employed as one of those computers.

Another reason that truck drivers won't find themselves out of a job tomorrow is that I've seen what a truck driver does. Working at UPS I saw that a truck driver will drive the truck and then have to load or unload the truck. They are also responsible for common maintenance, like fill the truck with fuel, check tire pressure, make sure lights are clear of mud and snow, clear the air lines of moisture, and more. When I was growing up on the farm the truck drivers were expected to back a truck up to a sorting gate and then chase steers onto the truck. They'd then drive to the auction house, chase them off. After the auction they'd chase another load of steers onto the truck, then haul them to a packing plant. Let's find a robot that can navigate all of that, chase steers, and not run over stupid farm kids that should not have been running around the parking lot in the first place

Then there are truck drivers that deliver frozen foods and other items to homes, that takes a skill set that robots have not yet reached. I'll hear an ice cream truck drive through the neighborhood occasionally, those people are still "truck drivers", no? Then there's all the other occupations that required skilled drivers, school buses, city transit buses, taxi and limo drivers, charter buses. We might put a robot in charge of moving cargo but I don't see anyone putting school children on a bus without someone to watch them, that person doesn't have to drive necessarily but they will be there.

That may even be true for cargo trucking. A person may not drive but they will ride along with the cargo to maintain the truck, load/unload cargo, handle paperwork, and put out fires. I mean real fires, ever seen a truck pulled off the road that's been blackened from brakes that over heated and started the tires on fire? Who's going to put out a fire on an driverless truck?

I can see this technology being adopted slowly. It will make the number of truck drivers shrink. If it means a truck driver can get a truck on the road, set the "autopilot" and then take a nap, then it could mean a reduction of as many as two out of three long haul drivers but those don't count for all professional drivers. People still need to drive buses, ice cream trucks, doorstep delivery, etc.

In other words, move along, nothing to see here.

Comment: Re:Good thing climate change isn't real! (Score 1) 293 293

I will believe man made global warming is a crisis when the powers that be start acting like it. A few examples:

- Secretary Clinton is *proud* of how many miles she traveled in an airplane to far off nations. She couldn't make a phone call?
- POTUS and family vacation in Hawaii at least once a year, a long way to go to play in the ocean.
- Congress would not approve nuclear powered ships due to costs, built oil fired ships instead. That's not how someone would act if they actually believed that global warming is the greatest threat to our nation.

My Ford truck is the problem when these people fly their dog across the country in a 747. Right?

Comment: Potential for abuse? (Score 1) 66 66

Which shape will get me highest the fastest? That's what I expect will be the most common question asked.

I see many possible problems with this, getting it FDA approved is just one of them. What will prevent someone from printing a hollow pill and stealing what what supposed to go in the middle to sell on the black market? The pills could be weighed but the pills could be filled with something of equal mass like sugar, sand, or something not so inert.

Will these pills be printed at the pharmacy? I seem to recall previous issues with poorly monitored medicine factories that did not require FDA oversight because they weren't "making" drugs as it was defined in law, they were merely mixing drugs that were made elsewhere and doing so in less than sanitary conditions. The FDA has failed us before and state agencies didn't feel compelled to pick up the slack, or was prevented from doing so by federal law.

Seems to me that there would be much less costly means to meter dosages than printing each pill individually. I can see this being used like it was described in the article, testing shapes in the real world before going through an expensive process of tooling up for mass production.

Edible 3D printing material could allow for making pills that carry all kinds of substances. Also, assuming high enough resolution on the printing process someone could make fake drugs. The little image on the label of what the pills inside a bottle should like like may no longer be sufficient to prevent theft of medicines, for example.

I can think of all kinds of legal and beneficial uses of technology like this too. As soon and someone reveals how this technology can be used for illegal activities in a public enough forum that some congresscritter sees it I suspect we're going to see a law passed that will ban or severely restrict this technology. I'll give the total freak out over the people that printed a firearm as an example of what kind of freak out to expect.

Good stuff, but the technology will very likely be held up by a government that cannot allow the public to have the freedom to experiment on their own.

Comment: Re:This is a headline, but not for those reasons (Score 1) 213 213

Being "unreliable" is much more than exploding transformers. One means to measure this is with capacity factors.

What is the capacity factor of a typical windmill? I see that with the best technology we have today wind power has just reached 50% capacity factors. Under ideal conditions wind could approach 66% capacity factors. Solar does much worse with 25%, but I'll give it 33% to account for future improvements and perhaps some negative bias in reporting.

Then there are the power sources that burn stuff and/or boil water. This we have oil, coal, natural gas, biomass, and nuclear. These have capacity factors that top out around 95%, average above 80%, and on the low end are about 75%. I'll be nice and give them a 66% capacity factor to again account for any bias.

Hydroelectric is probably king in this. Capacity factors that exceed all others. Given an additional pumped hydro capacity it can account for lack of capacity from other sources. With multiple generators on a single site there might be a single generator that is down but the facility is still producing power at or near rated capacity barring exploding transformers. As awesome as hydro is I can confidently give it a capacity factor that is so close to 100% that it will be 100% for this thought experiment.

So then how much does this electricity cost? Hydro and the burn/boil group all cost nearly the same. Hydro wins on this up to 33% because of capacity factor. Hydro also is reliant on geography, we've dammed up all the rivers worth a dam in this world, there is no growth in this.

Wind costs about the same as the burn/boil group by rated capacity (a bit more really but I'll be nice again) but with its production capability reliant on the weather and geography it takes two to three times as much of them to get the same power out. This is part on capacity factor and part on the fact that the wind blows when it wants, not when we need it.

Solar is the worst. With a capacity factor of even 33% we'd need three times the amount of capacity from a 100% source like hydro, and some means to transfer or store the energy to when and where it's needed. Ignoring capacity factor solar power costs three times what we get from burning and boiling. With capacity factors included it goes up almost three times again. If I stop being nice and start looking at reality the cost of solar is near to or above ten times what it would take if we burned and boiled our power into existence.

You can mix and match all of this if you like, hiding much of the costs of renewable in the noise that is real life capacity factors, but it works out that solar is always a loss. Wind is either a small loss to a break even. Hydro is always a win but then we run into issues of geography and "environmentalists" that would rather see people starve than have a few common bait fish killed in a hydro turbine.

These environmentalists will likely complain about any energy source that emits carbon. On the basis of carbon output per joule produced nuclear and hydro rule, nothing beats those two.

What good is a nuclear power station when it's transformer blows up? It's good in that we can easily afford to build redundant nuclear power generation so that loss of any one will not affect the grid. It's good in that with a capacity factor well above 66% that by building four power plants for every three we need that we can be well assured that the power will never go out.

(Don't bother trying to correct my simplified computations. I am well aware that my accuracy sucks. Point is that it should be close enough to the real world to show that nuclear and hydro should rule the world.)

Comment: Re:Bureaucrats (Score 1) 312 312

While it's possible that guns sold in Plano are used to kill people in Detroit it is much more likely that a gun used to kill someone in Detroit was purchased in Detroit.

That must take some dedication for a criminal, going to Texas to buy a gun and then return to Michigan to use it. If they've gone all this way to buy a gun then why not use it to commit a crime in Texas? I know why, because it's likely they'd get shot in the act.

Also, does this not show that gun laws in Detroit don't work? I mean they've already banned the guns but it does not seem to cut down on the crime. Let's take this to an extreme, no one may buy a gun except those approved by the government, and they may purchase only one after they've passed a background check. You know what happens then? I can tell you because that is roughly what the laws are in Mexico. What happens is you have soldiers in the army selling their guns to criminals. What are you going to do then? Ban guns from the army?

Comment: Re:Bureaucrats (Score 2) 312 312

It's funny you mention carrying... while 3 states allow largely unrestricted concealed carrying of a pistol (ie no permit required), another 39 are 'shall issue' states, which means so long as you meet the requirements and are not otherwise prohibited, you get your permit. I know hating on Texas (a state I have never been to/in) is a favorite pastime on /., it's kind of funny you mentioning them as that while a shall issue state, they are one of only six that prohibits open carrying if a pistol.

The number of states that do not require permits to carry a sidearm, concealed or openly, has increased to six recently. Kansas the most recent to do so.

Additionally there are 24 states that do not require a permit to carry a sidearm. This becomes 25 if Texas passes their open carry bill into law. The number goes to 25 also if you include the Texas open carry of long guns without a permit, and there are likely more states that do not restrict open carry of long guns but I am not aware of them.

More than half of the US states do not restrict the carry of firearms and other deadly weapons excepting that it must be done so visibly. Compare this to the other half that place severe restrictions on the carry of deadly weapons and I feel it is quite fair to compare the homicide rates of a US state with that of a European nation.

People forget that the USA is not, technically, a nation. The USA is a federation of nations. The USA has more in common with other federations, like the European Union, than with a unitary nation like France. This means that a wide variation in laws on things like weapons can occur. It does not follow to blame the murder rate in the USA on the gun laws in Texas when it's people in Illinois and Louisiana that are getting killed. If one wanted to make a logical argument then compare the murder rate of Texas to that of France and then compare the laws on guns.

What also steams me is that people will claim that the USA is at the top of murder rates compared to other "developed" nations. What of the murder rate in Mexico? Well that is not a "developed" nation, or so the claim goes. As the term "developed" nation has no real definition it is easy to claim that any nation with a higher murder rate is not "developed" like the USA. Did it occur to anyone that these nations are not "developed" like the USA because the people have been disarmed by their government? I mean it's real hard to keep people from stealing your stuff if they have no fear of getting shot as they trespass on your land.

I'll also point out how useless it is to require a permit to carry a concealed weapon. Concealed means concealed, no one knows who is carrying a firearm or other deadly weapon until that person chooses to reveal the weapon. People drive without a license and people carry weapons without a permit. In both cases it does not make sense to me to require law abiding people to get a permission slip from the government. If these people choose to follow the law then why should I care if they have government permission to do so.

Let that sink in a bit. We require a permit for what? So that people can show that they can follow the law? How about we do away with these stupid little pieces of paper and let people follow the law without first asking the government if they can follow the law? Requiring a permit to keep the insane from doing insane things is insane. A piece of paper is not going to stop the insanity. Getting rid of these pieces of paper would increase the level of sanity in this federation.

Computer Science is the only discipline in which we view adding a new wing to a building as being maintenance -- Jim Horning

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