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Comment: Re:It would speed up.. (Score 1) 362

by DanielRavenNest (#49474483) Attached to: Can Civilization Reboot Without Fossil Fuels?

> While they'd be intermittent

Solar thermal with hot-rock storage can be nearly around the clock, and modern vacuum-powder insulation can keep the rocks warm a long time.

Also, everyone seems to forget that big hydroelectric dams are massive structures. They aren't going anywhere for centuries. Replacing the generators and water turbines is a small job compared to pouring a million cubic yards of concrete. So even if you lost the tech level to run the dams, you could regain it relatively easily, and have lots of power to work with.

Comment: Re:Economics would be the problem (Score 1) 362

by DanielRavenNest (#49473975) Attached to: Can Civilization Reboot Without Fossil Fuels?

> the forward looking saudis will do what they have to do to be able to compete in the world

The Middle East and Africa are rapidly deploying solar panels ( ) They have an excellent climate for it, and they know the oil won't last forever. The Sun will.

Comment: Re:We have already figured most of this out. (Score 2) 362

by DanielRavenNest (#49473847) Attached to: Can Civilization Reboot Without Fossil Fuels?

Solar cement kilns have been demonstrated. The limestone and shale that are calcined to make Portland Cement don't care how they are heated, They just need to reach a high enough temperature for a while. We mostly use fossil fuels today for the process, but concentrated sunlight works fine.

Comment: Re:False Dichotomy (Score 2) 362

by DanielRavenNest (#49473807) Attached to: Can Civilization Reboot Without Fossil Fuels?

A combination of solar furnaces (mirrors and a steering mechanism to track the Sun), and thermal depolymerization ( ) can break down most anything organic into crude oil type feedstocks. That includes items like paper and animal byproducts. There is lots and lots of feedstock buried in landfills. So to reboot that part of civilization, you can use those ingredients.

Comment: Re:forking and "merging" hardwar designs (Score 3, Insightful) 46

by DanielRavenNest (#49473695) Attached to: The Makerspace Is the Next Open Source Frontier

In the aerospace industry, we had metadata around the actual design documents, and a process for incorporating changes. Some examples are:

* A drawing tree. A complete airplane or other complicated product had a top level drawing, that called out major assemblies (wings, landing gear, engine installation, etc). The major assembly drawings then called out sub-assemblies, in a tree structure, until you get to the parts level. Documents tied to a particular drawing (like engine installation procedure) got the same number as the drawing with a -002, -003, etc added, so you could track what they go with.

* Interface drawings and documents. Between assemblies you defined the interfaces between them - mechanical, dimensional, electrical, etc. You can't change your side of the interface before first consulting the people on the other side, and updating the interface data. That's how you ensure the pieces go together later.

* Requirements tracking. For example, the 747 landing gear has to support a takeoff weight of 880,000 pounds. Therefore there has to be a weights tracking process that assigns weight budgets to the various parts, and reports status back up the tree. Otherwise you can end up with a plane that's too heavy for the landing gear. Anywhere else there is a critical design value with contributions from various parts, you use this method.

All this metadata has to be passed around along with the actual parts drawings and software code. If you don't, then anything too complicated for one person to design is likely to need rework when the pieces of the design are merged.

Comment: Re: Makerspace Utility (Score 2) 46

by DanielRavenNest (#49473565) Attached to: The Makerspace Is the Next Open Source Frontier

Most makerspaces are hobbyist-level workshops. They don't usually have industrial grade software or fabrication machines available, because those are expensive. I'm working on the idea of a "MakerNet", where instead of a converted warehouse space with hobbyist tools and home-made workbenches, you have more commercial-grade machines spread around, either run as small businesses, or owned by groups of more serious hobbyists. For example, a $6,000 lathe might be split among half a dozen people. When you have a more serious project to do, you send the files for the various pieces to the respective machines that can make them. You also send payment, or deduct from a network account, to pay for the raw materials and other items you use up.

So higher quality machines, and people who regularly use them, therefore better output. But networked and distributed cost, so it is affordable on a hobbyist budget, and you have access to machines you can't afford on your own. Makerspaces can certainly be part of such a network. They would just need to have some machines and people that are able to do the better quality work.

Comment: Re:Offsite (Score 4, Informative) 443

That's what bank safety deposit boxes are for. Offsite, hard to break into, more or less fireproof through sheer mass, even if the building around it burns. Ask the bank about how thick the walls are, though. Class 3 is recommended (12 inches thick concrete), with additional outside fireproofing.

Comment: Re:Trade off tape vs HD (Score 1) 228

by DanielRavenNest (#49455113) Attached to: 220TB Tapes Show Tape Storage Still Has a Long Future

> Tape isn't dead, but it's not worth it for small quantities

The cheapest LTO-6 drive on NewEgg is $1500, and Sony has the tapes for $18/TB. External hard drives are running about $35/TB. So you need ~90 TB for cost crossover on sheer data volume, not considering usability and reliability. So I would agree, with those kind of prices, you might want to *start* thinking about tape when you get to 100 TB, because 1 drive isn't very reliable. It might work for backup storage, since you can get by with a broken tape drive for however long your backup cycle is.

Comment: Re:"everyone from PayPal merchants to Rand Paul" (Score 1) 67

by DanielRavenNest (#49455037) Attached to: MIT May Help Lead Bitcoin Standards Effort

> That is completely self-referential.

Nope. A "bitcoin" unit is just an entry of 1.0000 in the transaction ledger known as the "block chain". The block chain is just a bunch of files listing every bitcoin transaction ever. My copy is 36 GB at the moment.

The Bitcoin Network is what makes it possible to write new transactions into the ledger in a secure way. Secure means nobody can rewrite old entries in the ledger, and everybody can verify the contents are correct. Only the person with the private cryptographic key to an address can send the balance in that address to someone else. Without the network, the ledger could not be updated, making the balances recorded there useless.

Comment: Re:"everyone from PayPal merchants to Rand Paul" (Score 3, Interesting) 67

by DanielRavenNest (#49454999) Attached to: MIT May Help Lead Bitcoin Standards Effort

> First, a Bitcoin in of itself has no real-world value.

Neither does a UPS shipping label. It's the network of trucks and distribution centers that give the shipping token (the label) value. They are what enable moving a package from one place to another. That's a useful service, and hence people are willing to pay for the label.

Similarly, a bitcoin is merely an entry of 1.0000 units in a big distributed ledger (the block chain). It's the network of relay nodes and miners that give the bitcoin token value. They are what enable moving monetary value from one place to another. That's a useful service, and hence people are willing to pay for the tokens. Other parts of the ecosystem add more usefulness, and thus more value. Websites, wallet software, custom hardware, smartphone apps, exchanges, merchants who accept bitcoin, etc.

The transaction protocol also includes a scripting language, so you can make your money programmable. How useful is that? People have only touched the surface of what you can do with that capability.

Comment: Re:As part of the validation runs... (Score 1) 74

Except the Bitcoin Network already runs at 324 Petahash/second, and each hash computation requires many floating point operations - 128 rounds of applying a complex hash function on several hundred bytes of data. Aurora competing for bitcoins won't make a significant difference in the network hash rate, it is too puny. The network already runs at ~1 million petaflops by dint of custom designed mining chips that perform the necessary calculations in hardware, massively parallel in each chip. Then you aggregate server rooms full of these chips into a mining farm.

Comment: Re:Space debris (Score 1) 226

by DanielRavenNest (#49372199) Attached to: Chinese Scientists Plan Solar Power Station In Space

> I think a large problem is going to be space debris -

Nope. If you can build giant solar arrays in GEO, you can build small ones and attach ion thrusters to them. See the Dawn mission at Ceres and the Asteroid Redirect Mission NASA is proposing for examples. These space tugs can putter around and collect loose space debris. That however does not eliminate natural meteoroids. So your power satellite will need a maintenance program, or just accept a small amount of degradation as stuff hits it.

Solar arrays are thin, so most debris will just punch a small hole.

Nothing happens.