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Comment To answer that, the Republicans voted repeal (Score 2) 749

> We really can't tell the difference between Democrats and Republicans.... This sounds so Bush-like...

So you can know the difference on this issue, the Republicans voted to repeal the law. The law generates negative net revenue, costing more to administer and enforce than it brings in. Generally speaking, Republicans are against burdensome taxes, taxes that only cost money and don't increase revenue. That's more of a Democrat thing.

Comment spoiled, wasteful. 2000X as much RAM as Arduino (Score 2) 202

Get off my lawn, ya spoiled brat. The Pi has 2000 times as much RAM as the Arduino Uno, a million times as much as a Picaxe.

It really isn't necessary to run Windows 8 for embedded^H^H^H^H^H^H^H^H^H any applications. You can run a full operating system with a GUI, web browser, and onboard server in 8 MB. How much more do you need?

Comment Hmm, decimal in the wrong spot, or 10 MPH bullet? (Score 1) 188

I have to wonder if while trying to include everything in your calculations you misplaced an decimal or something, because 18 seconds is about NINE times as long as a quick estimate comes up with:

> System target distance is 1.2 miles. [6200 feet]
> Maximum effective range is around 6300 feet. ...
> muzzle velocity 3000 f/s,

6200 feet / 3000 feet per second = two seconds, at muzzle velocity

To get 18 seconds, the average velocity must therefore be almost 90% less than muzzle velocity. Average around 300 fps? That's just 200 mph AVERAGE. To start at 3000 fps and average 300 fps, the terminal velocity would be around 15 fps, or 10 MPH. I'm pretty sure a .50 round impacts the target at a velocity higher than a brisk walk.

Comment Re:Thanks for the detail (Score 1) 389

Putting aside feasible vs reasonable, etc., I think you've made your case quite well, as well as anyone could have. Based on my prior research, I was under the impression that photovoltaic simply wouldn't, couldn't ever happen other than special situations like a research station in the middle of nowhere, or some very low power applications. You've changed my view somewhat, which means something after all the research I've done. It appears street prices in 2014 are significantly lower than "national average" prices reported in studies from 2012. Thanks for the information.

Thanks also for your intellectual honesty. You started by saying I was full of shit about pumped storage, then when I "showed my work" you acknowledged that perhaps I was right. Few people have the intellectual honesty, or intellectual integrity, to do that. I admire and appreciate that.

Comment read-only OS doesn't execute random files (Score 1) 62

Suppose you have nastyshit.exe in your documents folder. How is it going to get executed? At boot, by a registry entry? Nope, because all the boot stuff, including the registry, is read-only. How did it get there in the first place? Not from malware resident on the system, because the system is read-only.

Comment only have two seconds (Score 1) 188

>. bullet waits to find it's tracking laser at the remote point, the bullet would have to be able to handle dramatically different angles, and know where the spotter is I would think), someone closer in could more easily track movement or switch targets on the fly.

That sounds more like a job for a drone loitering overhead. A .50 round will be in the air for less than two seconds.

Comment Make VM OS read-only unless updating (Score 1) 62

> suggests that using a VM obtains a measure of safety.

You can make it almost perfectly secure by mounting Documents from another disk or image and marking the operating system VM read-only, or snapshotted so it reverts state on reboot.

Toggle it read-write while you update the OS or install new software.

Comment botnets are still Windows. Set a router password (Score 1) 62

This botnet, like the one the malware based on, is Windows only. The botnet that was used to seed this one is also Windows only.

There have been two botnets that kinda-sorta might be interesting to Linux and Mac users. In one, if you used a Windows desktop to ssh to a Linux server, the infected Windows machine could reveal the user name and password that you used from Windows. In the other, some idiots left the default admin user name and passwords on their routers, some of which run Linux. Surprisingly, if the bad guy knows your username and password, that's a bad thing no matter what operating system you use.

Comment Re:Thanks for the detail (Score 1) 389

> So you've more or less demonstrated that pumped storage is infeasible. Why even talk about it then? Batteries are feasible.

You've demonstrated that batteries are at least possible. Feasibility is debatable, but you've moved the needle. Certainly, if you happen to be in the middle of the wilderness where natural gas isn't available, batteries could be considered feasible in those conditions at least. I learned something from that, thanks.

And you see pumped storage is certainly infeasible, so that's cool. Another closer to full understanding, and toward agreement.

> I'd like to see that simulation. I suspect it takes a supercomputer to render accurately.

It takes a lot of computation to render high precision and high detail. It all depends on what level of detail you want. If you model the topography of the US with 100 million "pixels" of elevation measurements, that'll take a lot more computation than using 1,000 pixels, such as the average altitude of each county. Flood calculators are popular for visualizing the effects of sea level rise, so I wouldn't be surprised if you've played with one written in Javascript on a page that talks about "if sea level rose 6 inches, it would flood ....". The simple Javascript ones don't have high PRECISION, but they may have reasonable ACCURACY. Since we don't care to distinguish whether 90% of Texas is flooded or 93%, much less which streets are flooded, an iPhone will do fine for the computation.

Comment just like any other contact, such as a lease (Score 1) 73

Suppose you lease a car from Toyota. You pay for five years up front. You now have the right to drive that car for five years.

Toyota goes bankrupt. They own the car, subject to the l lease to you, which reduces it's value to the company. Do you think the bankruptcy court is going order all leased Toyota's to be repossessed? Of course not. Toyota's ownership interest in the car is subject to the lease.

Same here. As soon as the deal is signed, that creates a restriction on the ownership of the patents, lowering their value. The value is reduced today, when the restriction is added. Five years from now, a bankruptcy judge isn't reverse time and undo the contract. On the other hand, if the company tried to join the association AFTER they filed bankruptcy, the judge would have to approve the new restriction on the assets and they may well block that.

Comment someone chose, wrote the story. What changed was (Score 3, Interesting) 109

> I remember a time when the news was reported and read. Nothing more nothing less. How people accepted the news was left up to the viewer, reader, or listener. Now we have flavored news,

In those happy times, an editor decided which stories he wanted to assign reporters to. Before "the news was read", someone wrote it, and the author had their biases. If you look at the news stories from many years ago covering two different politicians doing the same thing, you'll find the stories read quite differently depending on which party the politician was associated with.

The newspapers and television stations of yesteryear were just as interested in selling ads as today's are. I think the biggest difference is the level of honesty. Sean Hannity will TELL you that he's a conservative. Peter Jennings and Dan Rather pretended to be objective.

Comment Thanks for the detail (Score 1) 389

Thanks for the detailed reply. I see that you're skilled enough to calculate that your refrigerator-sized stack of car batteries could provide the power to pump several thousand gallons of water, demonstrating that batteries are a better way to store energy than lifting water is.

From your reported power usage, it sounds like you're probably single. If the rest of your figures are correct, we'd have roughly a refrigerator-sized stack of batteries _per_person_. Inverters are 0% efficient at no load (they waste 20 watts idling) to 90% at full load, so figure around 75% average efficiency, so 16-18 batteries per person rather than 12. Batteries lose capacity as they age. You don't want to replace your batteries every two years, but rather continue using them as their capacity decreases over five years, so we better go with 21 of those batteries.

The specific energy of a lead-acid battery is about 35 watt-hours per kilogram, or 64 pounds per Kwh. Our bank of 22 batteries is 193 Kwh at the battery when fresh, so you've got 12,352 pounds of lead and sulfuric acid to mine, then dispose of and replace every 5 years. Four billion pounds for the US. You're going to need a lot of large mines to get all that lead. You could do it, but it wouldn't be very good for the environment.

You asked me to show my work. Flood models are a bit complex, of course, but we can at least get a general idea by calculating the minimum and maximum possible, assuming ideal topography and worst-case topography. My original number was based on a calculation in the Proceedings of the National Academy of Sciences entitled "Powering the planet: Chemical challenges in solar energy utilization", but they might be wrong, so let's do a fresh calculation:

As per the Bureau of Land Reclamation (operators of Hoover Dam / Lake Mead) Hoover dam produces 4 billion kwh annually. Per EIA, the US uses 4,047 billion kwh. So we need 1,000 Hoover Dams. BLR says Hoover is 726 feet high and flooded 248 square miles. They also say the amount of water pushing on the dam would cover the entire state of Pennsylvania 1 foot deep.

The location of Hoover dam was of course chosen with some care - it's a good place for a dam, in a deep canyon. It's a place where you can build a dam 726 feet high, so the flows hundreds of feet down through the turbines, releasing a lot of energy. We won't find 1,000 to build dams over 700 feet high, but let's pretend we could in order to figure a MINIMUM possible amount of flooding. This is the minimum assuming ideal topography, where we have all the deep canyons we want. Hoover Dam times 1,000 is 248,000 square miles for the minimum. Dams go on rivers, of course, filling the river valley, so reservoirs tend to be long and thin, not square. If our reservoir is 10 miles across, it'll be 24,800 miles long. Oops, that's longer the distance around the earth. Let's make it 100 miles across, so it'll be 2,480 miles long, roughly the width of the United States. That's the minimum, pretending we have 1,000 deep canyons to fill hundreds of feet deep. A dam built in flat land will just create a shallow flood across the whole state. Worst case, assuming flat topography, would have the whole US under 70 feet of water. If you go into flood simulator software that's been loaded with the actual topography of the US and start placing dams on actual rivers and let it calculate the flooding based on real topography, you end up with about 80% flooded.

Comment 30.17 years, which is less than "thousands" (Score 1) 389

To be exact, the half-life of cesium-137 is 30.17 years. I was responding to someone worried about geological time frames. Certainly cesium waste / fuel should be stored safely for several years while it decays. In 90 years, 88% of the radioactivity is gone. That's something to pay attention to. It's not the "thousands of years" that the greenies used to claim, until most of them realized that "no nuclear" means "more coal".

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