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Comment: Re:Solar is here to stay (Score 2) 533

by DanielRavenNest (#49505313) Attached to: Utilities Battle Homeowners Over Solar Power

> Now they're just waiting for the products to arrive en masse.

For the Phillippines, that was 2014. They went from 3 MW installed in 2013 to 117 MW in 2014 ( ).

Worldwide, installations are expected to increase from 44.2 GW last year to 57 GW this year ( ). I think we have reached en masse.

Comment: Re:How this should have been prevented... (Score 1) 150

by DanielRavenNest (#49501573) Attached to: Incorrectly Built SLS Welding Machine To Be Rebuilt

> An alternate, plausible chain of events is that NASA originally, disagreed with ESAB and felt the floor fix was unnecessary in the first place

That's not plausible if you understand where the Michoud Assembly Facility is. It's next to New Orleans, and all of the ground around there is soft and swampy. If you are building anything heavy or that needs to be rigid, it needs heavy foundation reinforcement (thick slab, pilings, etc.).

Comment: Re:It would speed up.. (Score 1) 363

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) 363

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) 363

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) 363

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) 445

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) 229

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.

You can't take damsel here now.