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Comment Re:Nope they are clever (Score 1) 336

The liability shift from Visa's incredible marketing of the Visa Shield protecting you from identity theft with charge backs and banks calling you to tell you they're declining a suspicious gasoline charge in California after you've been using your card in Vermont all morning and since forever to "oh, someone else used your card? Well, sucks to be you. We can close the account and give you a new card number."

How do I turn this into a hot story to get the production crew salivating over running this on the evening news?

Comment Re:Too bad (Score 1) 198

Really? Because the installation of an AC and heat pump here is expensive, and the heat pump is wildly inefficient in the winter. It's good for the temperate season in the spring and fall, a total of about 3 months per year; there's 4-5 solid months where a heat pump trying to heat my house is either ineffective or a huge energy hog pulling in tons of electricity per unit heating. My most efficient option has been using a space heater in whatever room I'm in, keeping the rest of the house at 62F; otherwise I spend $300+ per month on natural gas at 1,400,000 BTU for my 1300sqft house.

You fail to mention how much of that solar thermal energy would simply be wasted (shoulder seasons, summer overheating) because you have no use for it.

I did mention the use of more efficient (20%-30% vs 14%-19%) sterling heat engines for power generation, but figure you'd use most of the heat directly and get little benefit. Sure, with a dT of 600C, you can pull 38% or even as high as 42% on a sterling engine; but at 300C vs 10C, you're going to get 20%, maybe 25%.

Solar hot water systems tend to heat the 150L tank to a maximum 190F before shutting down, in the first 2-3 hours of the day; a thermostatic mixing valve provides 120F-130F off the tank. This allows for less hot water usage when the water is hot, and stable temperature as the water cools, as people take showers at night or in the morning. Residential evacuated tubes have boiled coolant at temperatures as high as 350C in unusual conditions, but are commonly accepted to run as hot as 300C, and typically don't exceed 285C. It's considerable that a system running less than 5L of water in a loop can heat 150L to almost 90C from tap cold (10C) in under 4 hours.

In practice, people have a single 1.2m^2 panel here, running their hot water at 160F in the winter with short days, not quite enough to use hydronic heat. 2-4 panels would do it, at $500 each, with proper insulation.

Comment Re:Maybe 40k (Score 2) 393

Nobody is using the size of cells that Tesla claims to be interested in producing

Tesla uses 18650-size cells, specifically because they are the most common Li-Ion form factor in the world. If Tesla is planning on producing a different-sized cell at the gigafactory, please provide a link.

Comment Re:Spiral filter, and a Tardis (Score 1) 122

So let me ask: If the multiplexing is due to "the phase relationship between the oscillations of the field at different positions", may I assume that these systems would be very sensitive to multipath interference -- especially varying multipath interference, as in mobile devices? Is that why the only demonstrations I have seen involve point-to-point links in free space (where multipath would be minimized)?

Comment Re:Too bad (Score 3, Interesting) 198

Ocean warming is a bigger opportunity. Jabbing a thermal collector into a volcanic vent, rolling it through a sterling engine as a cooling system, with the cold side submerged in the cold ocean.

A lot of new, green tech is ludicrous. People want solar farms in the desert because of all the arid heat and lack of clouds, but discount the fragile ecosystem. Wind farms take up much more space than nuclear plants for the same power output. Hydrogen is difficult to store without supercooling, and is only a storage scheme and not a generation scheme, and only operates at 50%-80% efficiency. Hydroelectric is an environmental disaster.

Direct heat applications from solar-thermal water heating are about the only thing that make sense. Their efficiency is high, and their cost is low. A small, 1.2 square meter collector provides 3000BTU/hr, about 85% of a kW; I can fit over 20 of these on my roof at a sun-receiving angle and spacing, giving over 65,000 BTU/hr average throughout the day. My roof can produce 19kW of heat output, while I only need 3kW to stay warm or cool--the AC breaker is 30A, providing about 3kW of cooling.

A hydronic coil off the water heater, an absorption cooler, or so on can harvest the heat collected by less than $2000 of tubes and a total of $3000 of equipment to provide for about $2500 annual air space and water heating and cooling in my house. Excess generated heat could theoretically drive a sterling engine to produce a small amount of electricity, but the investment for more tubes to generate a useful amount of electricity would be unjustifiable; I can buy 100% solar electricity for 12 cents per kWh.

Thus, in just over a year, I can recover my investment in solar water heating by incorporating space heating and cooling, assuming I was in the market for a new furnace and air conditioner anyway--the furnace would be an air handler with electric back-up, vastly cheaper than a new gas furnace, offsetting the expensive absorption chiller. A $900 pellet stove would serve as a back-up. Overall, the setup would save an immense amount of electricity and natural gas.

Comment Re:Simple set of pipelined utilties! (Score 1) 385

Because they manipulate each others's data directly, instead of passing messages, thus opening the potential for one functional unit to pass and integrate unvalidated data into the memory space of another functional unit; and because a systemic failure in one unit will bring down the entire system; and because the security contexts of various functional units differ, thus differing policies may apply; and because you may restart or reconfigure one functional unit without interrupting the others.

It's the same question as why not to make bash, sed, perl, X11, and Firefox kernel modules.

Comment Re:Simple set of pipelined utilties! (Score 1, Offtopic) 385

Pipeline intercommunication aside, most large programs of any quality *are* formed from a bunch of small "do one thing well" utilities. They're commonly called "libraries".

Hit it dead on.

People don't want the added work of making things work. It's like building a floor: you need to strip off the old finish, reenforce the subfloor, ensure the floor is level, pour thinset, roll ditra, pour more thinset, lay tile, clean, and grout. Some folks leave old linoleum or hardwood flooring, claiming it's stable, and then pour self-leveling compound or just screw down concrete board, then put tiles on top. Some just cement tile straight to the floor, or pour SLC and cement the tile to that.

A properly built tile floor has many interfacing components. Tiles don't delaminate due to deflection or material expansion. Expansion joints at walls and proper intervals prevent buckling and delamination or cracking. The floor holds heavy appliances and large live loads, handles vibrations, and even impact. By contrast, a poorly-built tile floor tends to delaminate when temperature or humidity change a few percent repeatedly over 2-3 years, or crack tiles, or have grout rapidly decay from deflection and vapor infiltration.

Modern Web browsers isolate plug-ins and separate rendering threads (tabs) in separate processes with IPC. A runaway page still freezes the entire Chrome browser until something kills it; a crash in a plug-in or page doesn't bring down anything else. Isolate contexts allow security context changes: a simple render process can drop all access outside of specific system calls (openGL, etc.), actions on open file handles at current access (i.e. open for read, read-only--allows for giving ownership of a network socket to a process), and IPC to the parent (through sockets, pipes, shared memory, and so on); most of this falls under system calls to affect open file handles (i.e. an OpenGL object, an open file, an open pipe or socket).

It would make sense to have an init system, like SystemD. It would make sense for SystemD to provide an init like SysVInit: a simple, small, very basic program to read the init configuration and start the system. It would make sense for the init process to start first an init manager that resolves dependencies and tracks running start-up daemons, which examines the system on initialization and starts the mount point manager if not started (to ensure the temporary and runtime directories are mounted), and then begins bringing up other init system components, hardware managers (udevd), and so on, as per the configuration of the init system.

It doesn't need to be a giant monolith. It can be a collection of utilities all dependent on each other, running 3 or 5 or 15 services all communicating with each other, all to bring up the system and supply system state management. This is the simplest and easiest way to make a complex system, aside from the overhead of writing a new program from scratch to surround the collection of functions you want to use. You'd have to put the IPC stuff into a library, and work out how each program communicates with its dependents and dependencies and how it reacts when they're not around. Each task, however, acts as a readily-verifiable utility or daemon, and so does not interfere with understanding of any other task by mixing their code together.

Comment Re:Virtual Desktops (Workspaces) (Score 1) 545

People don't seem to get multi-desktop versus multi-screen. Nobody's figured out split desktop yet--I want two monitors with different desktops on each, changeable separately.

If I were a project manager for Microsoft, I would strongly push to port Gnome 3 onto Windows, folding the changes back into upstream. Gnome 3 on Windows, shipped as a standard option, would eliminate the usability issue between Windows and Linux: nobody would move to Linux after seeing the zoom-out view, application searching, and automatic virtual desktop features of Gnome 3. Windows on Explorer wouldn't be a crippling anchor to the 90s; Microsoft could just provide option for the next-generation Gnome 3 desktop.

The high productivity provided by Gnome 3's workflow--WinKey pulls up all your current desktop's windows, CTRL+ALT+[ARROW] moves you up and down, type to instantly search installed applications, drag-and-drop windows between desktops--is my major pitch for using Linux over Windows. That plus the Software Center (Pirate, Ubuntu Software Center, etc.) make Linux the top operating system in existence for people who actually want to use a fucking computer to get shit done.

I just wish Gnome 3's alt-tab swapped between windows, not application contexts (it's terrible, and doesn't swap back when you alt-tab twice); and that they hadn't made scroll wheel swap up and down between desktops, but rather left it as a zoom function on windows in the Activities view. If I want to scroll through desktops, I'll put the mouse over the desktop list and scroll; if I point at a window and scroll up, I want to zoom in. How is this difficult? Scroll wheel is a function of what at which you're pointing.

It's different when you're trying to argue with Apple, because you can't just download the Apple UI and tweak its source code. But Linux? You can port all those DEs to Windows (except Unity, which is a piece of shit). Marketing, boys.

Comment Re:The protruding lens was a mistake (Score 1) 425

Yeah, I guess it's not so bad if you assume that you're going to have a case, and that the case thickness will result in a flat back to the whole thing. I hadn't really thought of that.

Still, I think it's a bad choice. It seems kind of dumb to design your product with the idea that the dumb design won't be quite so dumb if you also buy a case.

Agreed. I never used a case with my iPhone, and a protruding lens would've been annoying and probably gotten caught on things on my pockets.

... but I do admit that I'm the only person I know of my friends who doesn't have a case on his phone.

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