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Comment Re:Fundamentally hard problem... (Score 1) 272

IMHO concentrated solar power is absolutely the way forward for the Southwest and other desert regions of the US that have 250-300 sunny days per year. There's plenty of land available, no scary chemicals are needed anywhere in the process, and the power output will naturally match the air conditioning power demand.

However, it won't work so well in more moderate climates - you can't concentrate sunlight on cloudy days at all, and a few straight cloudy days are all it will take to use up all of that latent heat in a molten salt tower. It might still be worth installing but you'll have to have standby capacity (perhaps in the form of natural gas generators) to match it and that unfortunately drives up the price.

Also, apparently a number of these plants are being built to use fresh water to help reject turbine waste heat, and that's unsustainable in the sort of desert environments where these plants make sense.

Comment Telephoto (Score 1) 258

Take the lens off the front and bolt the sensor to a used SLR camera lens. With the 10x or 15x crop factor, that old 50mm SLR lens will turn into a 500-750mm equivalent, and if you use a prime lens, it'll have even better low-light performance than the original wide angle lens. If you put it on a telescope, you can easily get into 5000mm+ territory, although it'll be very difficult to use without an expensive tripod and tracking system.

Comment Re:What? (Score 1) 260

While I agree that all captains (whether you're on a teeny little sailboat or a SuezMax container ship) should know how to use their fallbacks, I think that disabling GPS during military exercises is going to increase the probability that innocent civilians are going to accidentally encroach on those military ships during those same exercises. Seems like a bad idea.

For the most part, the cell phone networks don't need GPS to operate. Just knowing the location wouldn't be good enough for signal beamforming anyway because of all the multipath in urban environments. It's often the other way around - GPS location information is often provided by the towers to the phones. The phones use that info (whether acquired via real GPS or cell phone network assisted GPS) for E911 and for whatever smartphone apps want it. However, CDMA *does* need *very* precise time synchronization to work - and this is usually implemented via GPS receivers on each tower.

Comment Re:Indeed (Score 1) 862

People seem to want symbolic icons that represent the programs they want to run; they don't want to look through a long menu and read a bunch of text.

A lot of people want that - for themselves. However, most mere mortals eventually need some help with their computer and it's damn near impossible to walk someone through finding something just based on its icon over the phone.

Comment Re:People need to stop equating software to buildi (Score 1) 508

You can overbuild a house, it generally makes it stronger. You over code a piece of software it just adds to the number of possible points of failure.

In this context, "over coding" software refers to, for starters, defensive programming techniques (i.e. checking the return values of all the functions you call, fully validating external inputs, etc). It does not reduce the number of points of failure, but it does require the programmer to consider them and the gracefully handle them or transparently report the problems it can't handle. It does bloat the code somewhat, making it less concise, and it usually increases the amount of time required to make changes, but the transparent reporting of issues to the user significantly reduces the amount of time needed to debug flaws. Fewer bugs escape testing and the bugs that do escape can be accurately reported, are more likely to be reproducible, and are more easily fixed.

Comment Re:What other products (Score 2) 1019

Healthcare is first case of being forced to buy a product just for being alive.

Except that's not true. You're forced to pay income tax if you make income, which Congress was given carte blanche to do via the 16th amendment. You pay *less* income tax if you buy health insurance. But if you didn't make enough to get taxed that much, then you're not paying for this anyway (you are, however, still getting it).

Comment Re:750,000 hours MTBF. (Score 1) 238

the drives have other differences like a cost-reduced controller or different platter density, that makes it unsuitable for integration with the existing array.

I've mixed and matched hard drive vendors (usually intentionally) in RAID arrays for years; besides a little bit of performance, what am I missing? And if I need that little bit of performance, shouldn't I be short-stroking even more drives or using SSDs?

Comment Re:How much time before this is illegal? (Score 1) 164

I haven't seen anyone with the theoretical knowledge to work out the equations to prove or disprove the concept of leeching electricity from the ground

One place this is covered is the book "Antennas and Transmission Lines" by John A. Kuecken, in chapter 23, "Directional Couplers and Hybrid Junctions". Note that Slashdot doesn't allow for either unicode or sub/superscript so when you see "w", that means lowercase omega, and when you see "sub1" or "sup2" that means "subscripted character 1" or "superscripted character 2". The formula listed there for two sets of parallel wires (AB, the transmitting power lines, and CD, the parasitic receiver lines) is E = jIsub1wM where E in other contexts in the book is induced voltage on CD, j in other contexts in the book is a rotation operator (which appears to be identical in function to i, i.e. jsup2 = -1... in fact I'm wondering if it's really j or if that's just a confusing font), Isub1 is the current flowing through the power lines, w is 2pif, where f is the frequency (60Hz), and M is the mutual impedance per unit length AB to CD.

It goes on to say, "If line CD is properly terminated (RsubL = Zsub0) a current Isub2 = Esub2Zsub0 will flow, producing a reaction in AB: EsubR = +jIsub2wM = -Isub1(wM)sup2Zsub0. This equation is important since it leads us to the startling conclusion that the transfer of power from AB to CD proceeds not to equilibrium but to completion; that is, until the wave on AB vanishes!"

This section of the chapter also lists a couple references - "Techniques of Microwave Measurements" by C. G. Montgomery in MIT Radiation Lab Series Volume 11, "An Inside Picture of Directional Wattmeters" by W.B. Bruene in April 1959's QST magazine, "Low-Cost RF Wattmeter" by A. F. Prescott and W. C. Louden in GE Ham News, May-June 1961.

There. Clear as mud.

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