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Comment Re:Even if you go DC, stay at 120V (Score 4, Interesting) 597

(Continuing after brushing the touchpad posted it for me. B-b) ... equipment at that voltage. (Small systems are often 12V due to the availability of 12V appliances.)

But back to inverters:

Current inverter and switching regulator (they're pretty much the same stuff) technology is SO efficient that large PC boards in computing and networking equipment may run the power through as many as THREE DC-DC converters, because you lose less power to heat as losses in the inverters than you would to resistance running it a few inches through a printed circuit board power plane.

So the '"20-40% loss" number seems to me to be utterly bogus.

(Consider this: A Tesla automobile IS AC motors driven by inverters from batteries. A horsepower is almost exactly 750 watts. If they had 20-40% losses in the inverters, how do you keep the car from being on fire after a jackrabbit start? Let alone recover enough power on braking to reuse on acceleration to make a substantial difference?) If ANYBODY knows how to handle inverters it's Tesla. B-) )

Comment Even if you go DC, stay at 120V (Score 4, Interesting) 597

This is strange. "20 to 40% power loss" seems to be an awfully poor inverter; existing inverters are 4-8 % loss.

Rather than rewire every house in America, wouldn't it make more sense to just design better inverters?

Or just run at 120V DC, as renewable energy systems did (and occasionally still do) before so many appliances were AC-only that it made sense to use an inverter.

Dropping voltage means you have to replace the copper wiring with MUCH HEAVIER wiring - by a square law - to carry a given amount of power with the same loss - and thus wiring heating inside the walls, where it can set the house of fire.

Switching to 120V just means using DC-capable appliances and replacing the breakers (DC is harder to interrupt) and must-be-GFCI outlets (normal GFCI devices use a transformer to sense unbalanced load).

The 48V standard was about having a voltage that was low enough that touching it was typically survivable, so working on or near it is (relatively) safe. The boundary between the hard part and the easy, "low-voltage", part of the electrical code is 50V (BECAUSE of phone companies B-) ). Medium power (>1KW) home Renewable Energy systems tend to be at 48V so much of the wiring falls under the easier part of the code, and because of the availability of

Comment Re:Android IS a huge financial success. . . (Score 1) 344

If you're the sort of person who believes any and all business is merely a way to make profit and nobody who creates a company ever actually cares about the task they perform, then sure. Reality is more complex than that.

Re: China. iOS is in the minority in China. Even at the time of the iPhone 6 launch iOS market share was only 20%, but iOS market share always spikes around the time of a new iPhone launch, then falls back down in the other quarters. And China is a special case - Google isn't willing to play ball with the communist government so the services that make Android most useful are all blocked there. Apple cooperates so they can sell iOS as is, getting a built-in advantage. Despite this, Android still dominates.

Comment Re:Android IS a huge financial success. . . (Score 1) 344

From their perspective it'd be much worse than higher search rev shares. If Android did not exist, Google Maps would have been wiped out overnight on mobile when Apple decided to go it alone (against the wishes of their own userbase, no less). Android was never about making direct profit, it was always about ensuring Google was able to deliver their services directly to users. They were quite open about this from the start. And judged by this standard it has been an incredible, epic success.

iOS is on the way down anyway. Outside of English speaking countries and Japan it's in the minority everywhere. In some countries, especially European countries like Germany and Spain, the iPhone has been crushed.

Comment Not if they think they can get more work out of us (Score 1) 140

If this works, the monied and in-power will make this as illegal as LSD and heroin.

Not necessarily.

If the anti-aging drug(s) make people healthier, reducing the drain on the government pensions and enabling the government to push the retirement age out over the horizon, so the people will be working and taxed, they might prefer to have the drugs put into use.

Heck, they'd probably add them to the water.

Comment Re:Russian rocket motors (Score 1) 62

Russia would like for us to continue gifting them with cash for 40-year-old missle motors, it's our own government that doesn't want them any longer. For good reason. That did not cause SpaceX to enter the competitive process, they want the U.S. military as a customer. But it probably did make it go faster.

Also, ULA is flying 1960 technology, stuff that Mercury astronauts used, and only recently came up with concept drawings for something new due to competitive pressure from SpaceX. So, I am sure that folks within the Air Force wished for a better vendor but had no choice.

Comment Re:What a guy (Score 3, Interesting) 389

These career govt employees feed info to the pres, make recommendations, and fight for their interests. Even if a new pres wants to turn on a dime, Washington DC is a large ship that turns slowly.

Bingo. The old UK comedy "Yes Prime Minister" was a rather cutting illustration of this phenomenon at work.

What happens to someone when they become the prez? Enormous numbers of apparently experienced people begin telling you all kinds of secret things. They stress the importance of secrecy. They tell you about this plot or that plot. They say it's vital they get new powers and they not-so-subtly imply that if you don't help them Women And Children will DIE! And although it's left unstated you know perfectly well that if you don't give them what they want, you will see leaks in the press from anonymous officials that paint you as a prevaricator, as weak, as unconcerned for the lives of Patriotic Heroes And Their Women And Children.

The problem any US President has, and I daresay many other countries presidents, is that they are immediately submerged into a fantasy world woven from the agendas of the people around them mixed with their own pre-existing views, and those people are themselves also in a slightly less extreme form of a personal fantasy world and so on all the way down. A toxic brew of patriotism, belief in American exceptionalism, militarism and most of all pervasive classification means that it's impossible for a prez to penetrate the fog of misinformation that surrounds them. They can be manipulated into believing nearly anything because it would take an incredibly strong willed personality to say directly to the senior bureaucrats feeding them classified intelligence, "I think you are bullshitting me and I am going to personally audit your shit and prosecute you if you're lying to me".

Obama is very much NOT a strong willed personality. He sees himself primarily as a reasonable man who finds compromise between different factions. This makes him easily manipulated: all it takes is for people who agree to present him two apparently opposed positions - one extreme and one very extreme - and Obama will reliably pick something that is quite extreme. And the officials around him know that.

In hindsight it should have been obvious. Obama has no real track record of achievement in politics. He supported no particularly controversial positions, or showed any particularly clear thinking. Compared to Bush he seemed like a genius of course but Bush was a fucking man child, so that wasn't hard.

For that reason, Rand Paul fans might be disappointed if he won. I don't expect he would be able to accomplish as much change as people would like.

Almost certainly not. But it looks like Rand Paul is made of stronger stuff than Obama. Paul consistently argues for positions that piss off most of his party. He seems able to come to conclusions about things himself regardless of what other people believe. He seems to have fairly strong principles. He doesn't come across as the sort of wishy-washy people person that Obama is. If there's any US politician that actually might tell the people in his secret briefings "stop bullshitting me or I fire you", it's probably Rand Paul.

Comment Re:None. Go meta. (Score 3, Insightful) 336

That sort of logic holds true when moving between languages that are very similar. The transition between Python and Ruby or Java and C# spring to mind.

However if I need a C++ programmer and need one pronto, I'm not gonna hire a guy who has only JavaScript on his CV no matter what. Learning C++ is not merely learning a different way to create an array or slightly different syntax. To be effective in C++ you need to know how to do manual memory management and do it reliably, which takes not only domain knowledge but more importantly: practice and experience. You need to understand what inlining is. You very likely need to understand multi-threading and do it reliably, which takes practice and experience a pure JS guy is unlikely to have. You need to be comfortable with native toolchains and build systems: when the rtld craps its pants and prints a screenful of mangled symbols you need to be able to understand that you have an ABI mismatch, what that means and how to deal with it. Unfortunately that is mostly a matter of practice and experience. You might need to understand direct manipulation of binary data. There's just a ton of stuff beyond the minor details of the language.

Could the pure JS guy learn all this stuff? Of course! Will they do it quickly? No.

Democrats

Obama Asks Congress To Renew 'Patriot Act' Snooping 389

mi writes: President Obama has asked the Senate to renew key Patriot Act provisions before their expiration on May 31. This includes surveillance powers that let the government collect Americans' phone records. Obama said, "It's necessary to keep the American people safe and secure." The call came despite recent revelations that the FBI is unable to name a single terror case in which the snooping provisions were of much help. "Obama noted that the controversial bulk phone collections program, which was exposed by National Security Agency contractor Edward Snowden, is reformed in the House bill, which does away with it over six months and instead gives phone companies the responsibility of maintaining phone records that the government can search." Obama criticized the Senate for not acting on that legislation, saying they have necessitated a renewal of the Patriot Act provisions.

Comment Context (Score 3, Informative) 62

This ends a situation in which two companies that would otherwise have been competitive bidders decided that it would cost them less to be a monopoly, and created their own cartel. Since they were a sole provider, they persuaded the government to pay them a Billion dollars a year simply so that they would retain the capability to manufacture rockets to government requirements.

Yes, there will be at least that Billion in savings and SpaceX so far seems more than competitive with the prices United Launch Alliance was charging. There will be other bidders eventually, as well.

Comment Re:F/OSS reality (Score 1) 167

If all you say is true then what is your reasoning for why Linux adoption is still in the low-single-digit percentage?

A combination of: it's long-standing reputation for user-hostility, a general lack of interest in "geeky" things, fear of the unknown, and the fact that you have to go wayout of your way to get a copy.

True story:Iwas talking with a friend, who is a school-teacher, at a bar, and she mentioned how sad she was that the school was shutting down their Ubuntu lab. A while later, Isaid something about Linux, and she said, "Oh Ihate that." So Isaid, "if you hate it, why are you so sad the school is shutting down the Ubuntu lab?" And she replied, "Oh, is that Linux? Ihad no idea! Ithought it was that system where you had to type to make the computer do anything." :)

Comment Re:It's kinda cute (Score 1) 445

Maybe someone should tell them that nobody outside the US even remotely takes that "controversy" serious?

I don't know if you realize this, but "outside the US" is an area that contains countries which are not among the developed nations, and in poor countries with limited access to schools and low literacy rates, a lot of people do take the controversy seriously. Heck, Turkey, which is actually part of the EU, has a ever-so-slightly higher rate of evolution-rejectionism than even the US does. (Although it's the only country in the EU with more anti-science idiots than the US.) :)

Brazil also seems to have a lot of science-rejecting creationists. India, perhaps surprisingly, does not, but then evolution isn't actually all that incompatible with Hinduism. Can't find any data on China or south-east Asia or the rest of South America.

Comment Re:No code? Political Science? Techwriter? (Score 1, Insightful) 117

Yes, we're programmers, so all those so-called experts in user-interface design should just shut up. We don't need usability studies! We wrote it ourselves, and pressing Alt-X and then typing "frobnitz" works and is memorable for us. Why should we adapt to using these stupid mice the way lusers would expect?

Sure, intelligent programmers might realize that there are domains involved with computing and software projects that don't directly involve coding skills (like user interface design, or real-world use cases, or, god forbid, the realities of social interactions with others), but those are all quivering gamma rabbits who cower before us mighty Social Injustice Warriors who lurk in our mothers basements, and never have any interaction with women whose names don't end in .jpg!

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