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Comment Re:so... (Score 1) 260

The input is DC so there is no need for low frequency input decoupling

Unfortunately, that's not true. The output is AC and the input-referred current will reflect it, i.e. will be quite high when the output reaches its highest (340V). Since the input source has an equivalent internal resistance of 10Ohm and would droop too much, some bulk capacitance is needed to provide these 120Hz current surges.

I agree with you that the design revolves around the placement of power components (capacitors, inductor, power switches and some sort of heatsinking), then the control circuitry be crammed in the spaces between them.

Comment Re:so... (Score 1) 260

Having read the actual spec, I realized that my question was stupid. Input voltage is 450V, therefore the inverter is just a full-bridge DC/DC converter

The challenge is actually perfectly doable, with the only difficult points being the size of the switching inductor and the input bulk (most likely tantalum) and output filtering (must be ceramic) capacitors. IOW, the winner will be the one with the best connections to component manufacturers.

Comment Re:it depends on what "skilled worker" means. (Score 1) 401

However, there are about 600,000 H1B workers in the USA. How many of these do you believe have the skills only found in comp-sci grad programs, or more to the point, how many of those don't have and don't need grad school comp-sci skills?

One thing I never understood is why so many posters on /. believe that Comp-Sci is the only highly technical field that matters. H1B visa holders are many times technically-educated people who have nothing to do with programming (i.e. Chemistry, Materials Physics, EE etc).

The Sun does not revolve around IT, so why are we suggesting it does?

Comment this guy is out of his mind (Score 3, Insightful) 228

Not only it's not obvious what "better" means when baking is involved, but he's showing his Microsoft roots here, stupid "improvements" that make the whole system break so much easier.

It's a known fact that most "modern" residential ovens, the ones with displays, lots of buttons to set baking programs etc, should never use the self-clean cycle. The thermal insulation is not good enough to protect the electronics (a.k.a. control board) and the oven fails, typically after a high-heat cycle (the self-clean reaches 700-800*F). This is equally true for GE and Whirlpool as well as for Viking and Ilve.

Adding more electronics to a hot environment is asking for more and expensive trouble.

Commercial appliances are better built though, are they Myhrvold's target? In any case, his post is just a petulant rant showing overkill application of technology, just because "he can". Zapping mosquitoes with laser beams sounds more realistic...

Comment Re:Why not also Egypt? (Score 1) 40

However, the general consensus is that Egypt borrowed the agriculture invention, and rather late at that (~5000BC), not the other way around.

The Egypt's ancient culture has been focused on the Nile *exclusively*, they did not care about the delta and sea-faring until they started meddling in Middle East affairs (1200BC or so). The first major sea port has been founded in Classic Antiquity only!

Comment Re:My friends don't fart... (Score 4, Interesting) 148

Farting is caused by the inability of our intestine to break complex sugars (lack of specialized enzymes), examples of which can be found in legumes. These sugars then reach the gut, where bacteria have no problems breaking them, releasing gasses in the process.

There are even pills you can take with your food (e.g. when eating beans) that provide the missing enzyme so that you won't fart. In US, Beano is probably the most popular one.

You won't fart just because you ate a chocolate bar. And b.t.w., these complex sugars are not sweet, therefore there is no connection between eating sweets and farting.

Comment Re:Human's a very good at not dying (Score 1) 483

It must be a sad world in your neck of the woods or you're plain trolling. Gun ownership is much lower in Europe, you've been watching too many action movies "located" there.

I also don't see why you felt compelled to bring in the 2nd; the topic had nothing to do with it and nobody referred to it. Just take a deep breath and cool down.

Comment Re:Seamless fallback (Score 1) 126

Unfortunately, the major carriers keep scaling down the voice repeaters to increase the data bandwidth instead. The network I'm on (Sprint) is getting worse and worse for pure voice calls, with new dead zones appearing very frequently - all in a metropolitan area.

Soon the voice service will be so bad you'll be happy to permanently switch to VoIP.

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