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Comment Re:Why DC is a greater fire risk (Score 1) 376

Fires are only one small part of the issues with DC arcing. Simple things like switches need to be sized significantly larger to break a DC arc compared to an AC arc. Fuses become larger, switch mechanisms need to be stronger to overcome the potential for welding shut of contacts, and you don't get to do any fancy solid state switching such as switching on AC zero crossing which has a lot of applications for combining multiple sources of supply and switching between them.

Comment Re:If you're getting 50% efficiency... (Score 1) 376

A crap one will give you 80-90%. This is a simple and known engineering problem with well published and cheap solutions.

Old metal transformer + rectifier + linear regulators achieved better than 50% efficiency and those are now banned in some parts of the world due to poor efficiency.

Comment Re:50% is lost in AC to DC conversion? (Score 1) 376

Single voltage with known source and target load requirements are absolutely trivial to get into the 90%+ efficient range. In fact making such a charger was part of a 3rd year assignment at my university and we had to demonstrate a measurable 95% efficiency. It all came down to part selection, and they were selected by a formula. The theoretical values almost perfectly matched our final chosen values to achieve what we needed.

Efficiency becomes a problem when you start wide ranging your inputs or your outputs. I.e. you need 5-48V DC inputs (120V - 230V isn't too hard), or you need a wide ranging current output .05-5A all while staying within a tight tolerance. Then efficiency becomes a problem as you hit some trade-offs.

As a side note a transformer + rectifier + linear voltage regulator is more than 50% efficient. These are now banned in Australia due to efficiency laws.

Comment Re:Oh Great! More Central Planning! Just what we n (Score 1, Insightful) 374

I still am, it isn't their job to pick winners.

No but their job is to serve the greater good and legislating on energy efficiency in that regard is no different from mandating health and safety standards, or telling the local coal plant that they can't simply produce cheaper energy by dumping sludge into the river rather than disposing of it correctly.

Every single decision ever made by a government results in picking winners, whether specifically by technology as in this case, or by trade agreements, setting minimum standards, or in some cases even granting specific monopoly by flat out funding a project using tax payers money.

Comment Re:Privacy (Score 1) 277

And right there you underestimate the influence and use of a social network, doubly so with your comments on jobs.

Facebook is used for more than just posting pictures, it's used for event co-ordination. Everyone of my friends who have decided to quite Facebook out of some principle eventually came back. Why? Because no one saw them anymore. They disappeared off party invite lists, they didn't keep up with other's lives and missed big things like people moving away, etc.

For many people Facebook is far more important than email, or even phone. I would say 3/4 of my messages I get via Facebook rather than SMS. I just went through the job market and the job I actually got I got over LinkedIn, not a career website or via email. One company I applied at flat out said they only advertise jobs on LinkedIn at the moment as that gives them the coverage and applicants they need and sure enough they had all their job postings on the social network for the unemployed.

Now this all very demographically specific. But for many people out their social networks are their ONLY means of social communication and quitting that social network is akin to no longer talking to any of their friends.

Comment Re:lower the reported sample rate (Score 1) 89

Because it's the tip of the iceberg. If you make something that's designed to allow users to track their usage then it could be used to formulate an ID by a computer as well. Sure the combinations may be higher, but combined with your OS, Browser version, plugin list, screen resolution, language, ... snip ... remaining battery life, you end up with a pretty unique fingerprint without any individual item being very unique to you.

Comment Re:Barking at the wrong tree (Score 3, Interesting) 108

The point of much of social media is not to share links but to replicate content and isolate it from it's original context. You're sharing content not necessarily hyperlinks.

Just look at Facebook this week. Yesterday a video was released by DC Shoes about a daredevil who rode a wave on his motorbike. and hyperlink

You won't get that link anywhere else. I had to google it. That's the original content. Yet my local news had a link to the video on youtube, naturally embedded in the news page. Facebook today has the video itself shared multiple times on their platform without any link to the outside world what so ever each share also removing context of the previous share. The video on my friend's page has 3 comments on it, the video on Motorcross Australia's page has 400 comments on it. Each of these are now detached despite being the same content from a single originator who is never linked to.

Comment Re:Barking at the wrong tree (Score 1) 108

The process had absolutely nothing to do with breathlessly tweeting out every gasp in the real estate market and everything to do with being specific.

You were buying a home. Many people don't. Many people buy investment properties and will absorb those tweets like the weekly junk mail advertising the latest low price gadgets at the local electronics store.

"The number of Unix installations has grown to 10, with more expected." -- The Unix Programmer's Manual, 2nd Edition, June, 1972

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