Sodel · HackerTrans

Sodel

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Halcyon Days: Interviews with Classic Computer and Video Game Programmers

dadgum.com

1 pointsby Sodel13 ปีที่แล้ว0 comments

Inline-crypt.el: simple inline AES encryption for emacs

github.com

2 pointsby Sodel13 ปีที่แล้ว0 comments

ARM announces ARM v8, with 64 bit addressing

osnews.com

3 pointsby Sodel15 ปีที่แล้ว0 comments

A lot of effort to prove that e^(*pi) + 1 = 0 is ugly

symbo1ics.com

6 pointsby Sodel15 ปีที่แล้ว2 comments

The Noel Smith-Wenkle Salary Negotiation Method

infohost.nmt.edu

4 pointsby Sodel15 ปีที่แล้ว0 comments

comments

3 ปีที่แล้วdiscuss

Very interesting indeed. This reminds me of a (relatively) recent standard for distributed industrial process control.

For industrial process control, the IEC-61499 [1] standard introduces an architecture where the program and its function blocks are independent of where the components actually run.

I don't believe automatic distribution of the components to different devices is included. But, it allows setting up function blocks and their interconnections, and then distributing function blocks between devices. Inter-device communication is included in the standard.

Compared to standard PLC programming (IEC-61131), 61499 adds events to the function block diagram paradigm.

I don't think this standard os popular yet, but I've always wanted to give it a try.

4diac is an open source implementation.

[1] https://en.m.wikipedia.org/wiki/IEC_61499

[2] https://www.eclipse.org/4diac/

3 ปีที่แล้วdiscuss

I mostly agree with your points except to say that, even if Oracle is not active in the project, the risk is real as long as Oracle owns any of the copyright for any ZFS code.

The USL vs BSDi litigation over BSD ultimately came down to a handful of source files out of 18000. ( https://en.m.wikipedia.org/wiki/History_of_the_Berkeley_Soft... )

I wouldn't talk badly against ZFS, but I would not roll any dice with Oracle as a copyright holder.

6 ปีที่แล้วdiscuss

Someone will probably need to correct me, but here's how I understand it.

Proteins naturally fold into a shape where they have the lowest "potential energy". There are several useful metaphors to explain what "lowest potential energy" means and why the proteins are attracted to the shape with the lowest potential energy.

In "the real world", an object's "altitude" is a form of potential energy. A ball on a hill will roll down hill until it settles into the lowest valley it can — the place where its potential energy is lowest. Balls roll downhill to the place of lowest potential energy, and proteins fold into the shape in which they contain the lowest potential energy.

You can also think of a fresh protein as a stretched out spring. The stresses in the spring from being stretched out of shape are a form of potential energy. The spring will contract until it is completely relaxed so there is the minimum amount of "springy" potential energy remaining. Springs contract into the shape that is most "relaxed" and has the lowest potential energy, and proteins fold into a shape having the lowest potential energy.

If the protein was to fold into any other shape, there would still be some potential energy left in the protein that could be relieved if only the protein could get itself folded into the "correct" shape. If the rolling ball gets stuck on a rock or the spring gets snagged and can't completely relax, both objects would be stuck with a higher potential energy than they would if the ball reached the bottom of the hill or if the spring were allowed to fully relax.

Hopefully this explains why there is a single shape that proteins are most attracted to when folding. But, it doesn't explain why other shapes are somehow "invalid".

Proteins are like pieces of cellular or chemical "machinery". Like the parts of a mechanical machine, the protein's shape is part of what defines how the protein works, what it can "do", and how it fits together with other pieces of the cellular machine. And, since "correctly" folded proteins always have the same shape, "machines" can be built with them.

When proteins are misfolded, they have a different shape from the shape that all of the other machinery expects. Like a gear without teeth cut into it, the misfolded protein doesn't perform the function that it, as part of a cellular machine, is supposed to perform. The protein might "jam" the machine up or even cause the machine to malfunction and start doing something completely unintended.

I hope this comment is correct enough and clear enough for an ELI5 — though it might be more of an ELI15.

10 ปีที่แล้วdiscuss

I've got two hobby projects on the go.

I'm building a steam power plant simulator for students and trainees that won't cost upwards of $100K for a site license. It also has a plant builder interface, which lets anyone place and connect equipment, piping, instrumentation, and controls. Then, they can run the plant like a real operator would from a control room.

When I was at school for power/stationary engineering, we all wished we could use something like the school's simulator at home. So, maybe I'll get to fill that niche. (And, nothing out there has a do-it-yourself plant builder!)

I have mostly-complete prototypes done for the builder interface and numerical simulator. I like that it keeps the theory that I learned at school nice and fresh.

Also, I bought a gas turbine engine on eBay, and I'm working with a friend to get it running. We got an oil system hooked up yesterday, and we spun it up with the starter motor and a car battery. Lots of fun!

10 ปีที่แล้วdiscuss

First of all, I love this.

One nagging thing in my mind, though, is how easy it seems it would be for a Three-Letter Agency to backdoor LE to pieces. Then again, I guess that's nearly just as true for any CA out there.

(I don't mean to pooh-pooh this useful service! And, if there's any interloper-mitigation going on that I don't know about, I'd be happily put straight!)

11 ปีที่แล้วdiscuss

You appear to be assuming (not being a mind-reader, whether you actually are or not is of course unknown to me) that QNX would automatically be used in server farms if it was high throughput; and, since it's not visibly used there, it is not high-throughput.

(As an aside, I'll grant that even a high-throughput microkernel seems likely, to me, to have a lower throughput relative to a more tightly-coupled monolithic kernel. That's just one of the architectural trade-offs involved here.)

As I see it, there are technical (e.g. hardware drivers, precompiled proprietary binaries) and social (e.g. relative lack of QNX expertise = $$, proprietary licensing) reasons for many people to choose one of the more popular OSes, running monolithic kernels.

I can't say what's technically superior, but even if QNX was, nobody's a dumbass for choosing something else -- and I don't think the fellow you're replying to was saying so. There are, of course, reasons and trade-offs.

An OS's adoption is a social thing, and proves nothing technical about it. If it wasn't for licensing (a social problem), BSD might have taken off, and Linux been comparatively marginalized.

Just sharing my perspective here.

11 ปีที่แล้วdiscuss

From that article, I get the impression that the 6-month limit only applies to direct submission of prior art to the Patent Office. Patents can still be invalidated by prior art in court.

11 ปีที่แล้วdiscuss

One friend of mine essentially refused to take breaks after school. He'd get home and immediately start working on the day's homework. It would frequently take him until after 9 o'clock to finish up work that shouldn't have taken anywhere near that long. I know he's an intelligent fellow, and not prone to distraction. He'd just get stuck.

I'm /certain/ taking a break would have gotten him into a fresh mindset, and let him finish it all up faster. And, if I had /not/ put some hours between getting home and doing my homework, that it really could have taken me many hours to finish.

Just one speculative data point, but there it is.

11 ปีที่แล้วdiscuss

Hey, that's a really cool idea! Using an asteroid as its own propellant.

11 ปีที่แล้วdiscuss

Agreed. Posix xargs is bafflingly inane. GNU xargs, at least, supports `xargs -d '\n'` to regain some line-oriented sanity. I prefer to use GNU parallel these days, though, since it's line-oriented by default and a bit more ergonomic.

11 ปีที่แล้วdiscuss

Sorry if this is pedantic, but actually:

    find . | grep 'abc' === find . -name '*abc*'

    find . | grep -i 'abc' === find . -iname '*abc*'

The -name and -iname options do a verbatim file name check if you don't include those wild-card asterisks. I've been inconvenienced by having to go back and add them often enough that this is burned into my brain. :-)

11 ปีที่แล้วdiscuss

The is the operating system that I always wanted to make, without having the time or talent to pull it off. Just wonderful.

11 ปีที่แล้วdiscuss

Some folks have already moved on to a lost PLA casting process. I've seen some pretty decent results.

http://3dtopo.com/lostPLA/

11 ปีที่แล้วdiscuss

I was lucky enough to get a tour of their facility last June. One half was assembling and testing the most colossal plasma injection guns, driven by the biggest capacitor bank I have ever seen in my life.

The other half of the facility contained the anemone-shaped plasma compression chamber from all their promotional images. (And far more impressive than the dinky prototype from the article above.) They had a shelf full of cracked steel pistons, and I'm still not sure how they plan to solve that problem when the full-scale machine uses 200 of them instead of just a dozen or so.

(An aside, if anyone from General Fusion is reading this: my inventor friend suggested shooting slugs of molten lead into the molten lead core, instead of using the current steel-piston approach.)

I guess I'm just saying that between the facilities, and what our host (one of the project managers) was talking about, I'm satisfied that they're not dawdling. These are just some inherently hard problems they're working on.

11 ปีที่แล้วdiscuss

Isn't this the definition of "unauthorized access", as far as the law is concerned?

I'd be less uncomfortable if you had to deliberately choose which friends to share a certain network with. "Share with this person", or something.

11 ปีที่แล้วdiscuss

I recommend adding something about static type checking to the list at the top of Crystal's homepage. I saw "never have to specify the type of...", and believed it was another dynamically typed language.

I actually didn't know it had static type checking until I had closed the tab, and glanced at this comment you posted here. (I know, I didn't read very far in the linked page.)

That aside, it looks neat! :)

11 ปีที่แล้วdiscuss

I'm excited about cadquery for this reason. It's a Python library.

https://github.com/dcowden/cadquery

11 ปีที่แล้วdiscuss

I'd worry about the same thing. Government subsidy sure hasn't made education any less expensive.

(Education and public housing aren't quite the same thing, I know, but I'd still want to see some active work to prevent the same outcome.)

11 ปีที่แล้วdiscuss

Very odd placement, but the code examples are posted under "screenshots".

11 ปีที่แล้วdiscuss

First off, thank you for mentioning Cadquery and Verb. I've never heard of either, and they're both interesting. Cadquery in particular looks very promising.

Solvespace is a genuine joy to use. If making chamfers, path-based operations, and other such features were better supported, I'd gladly make it my primary CAD package.

It was released as open source pretty recently. I really hope some more development takes off.