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Comment Re:"flight proven"? hahah (Score 1) 110

You are mistaken in thinking that dense fuel is something nobody else wanted to try. USSR did that in the 1970ies, they have even developed a special high density fuel (syntin) but stopped using it in the 1990ies due to high cost of it.

Sorry, I should have known that most readers would not be up to speed on what SpaceX has done, and I should have explained densification as they've done it. While the Soviets used a chemically denser hydrocarbon, SpaceX has made conventional LOX and kerosene denser by cooling them to a lower temperature than is necessary just to liquify them. LOX gets almost 10% more dense and kerosene about 2% more dense, and they have changed the size of the LOX and kerosene tanks relative to each other so that the ratio required for combustion remains the same. This is just through refrigeration, rather than the more expensive process of molecular synthesis employed by the Soviets.

Comment Re:Am I The Only One... (Score 1) 40

... who laments the loss of the humble 2.5" HDD [or, at the very least, a removable 2.5" SSD] from a laptop or netbook these days?

I understand why companies are moving away from the idea of removable, normalized-size drives [it's cheaper to make the machine when it's just a daughter-board] but the loss of flexibility really chafes.

There are standards for smaller flash drives, but the situation isn't looking quite universal. One thing that bugs me is the smaller version of SATA in 1.8'' drives; the shared connector between 3.5'' and 2.5'' drives was an incredible improvement over the PATA situation.

Generally, I find it dumb when "desktop" and "mobile" components are artificially segregated by the use of different connectors etc., while it's really the same computer tech underneath. I like to use quiet and low-power stuff for my non-mobile needs, basically because I have to pay for the electricity and listen to the fans myself. Also, you'd think it were cheaper to build fewer different models of everything. SATA for 2.5'' and 3.5'' was a brief moment of sanity, and now we're in the same mess again.

Comment Re:Lambda's plug poor OOP language design (Score 1) 346

But if you could attach your own OnClick method to the button, only one method can be called when the user click on the button, which would be a huge problem for many gui objects.

Put the calls to the other ones in that method. Treat it as a stub method.

And I am not against a "listener registry" or whatever one wants to call it, it's just that a dev shouldn't have to deal directly with it for the vast majority of typical UI coding. Have a convenient front-door for the vast majority of "customers", and a back-door for specialized fiddling. You could stuff a hundred additional on-click events for that button into the listener registry if you wanted. A default on-click method doesn't prevent that. (Hopefully there is a priority code to control order of handling.)

Also, one could put a general event handler on the button's container, and do the other handlers that way, using reflection or environment info to know what widget and what action triggered it.

There are many options without having to deal with lambda's. Would you like to present a specific use-case to explore further?

(I've been trying to invent/define a table-oriented GUI engine that is mostly language-neutral. Most events can be handled using tablized attributes instead of imperatively coded behavior. Everyone's just used to hand-coded behavior out of industry habit. It's poor tool/labor factoring to re-invent a GUI engine for every different programming language. A good language-neutral GUI engine could be attached to any language.)

Comment Proponents [Re:Really?] (Score 1) 42

"If you tried [RoR], and cannot learn it, then programming just might not be for you"

I've seen too many similar statements from proponents of various frameworks/tools/languages/paradigms: "If you don't get X, you are stupid and should be flipping burgers."

After more than a decade of debating so called Golden Hammers and probing their justifications, I've concluded that people just vastly think differently and there are many ways to shave a cat (skinning them is too mean).

Some techniques just resonate with certain brains better. There is no reason to make it personal or mean.

I've met other Table Oriented Programming thinkers ("Tablizers"), and they love it also, but selling TOP to others has fallen flat.

They seem to prefer coding attributes (or what should be attributes) into what TO ME is verbose and hard-to-read code. But they LIKE reading that verbose code and even seem fast at it. Boggle. It's like Fred Flintstone preferring to stick with his feet-powered-car instead of getting a Honda. If Fred can get around well and quickly in his Footillac Deluxe, I guess I shouldn't care, as long as he doesn't force his car choice on me.

Hopefully each can find or make a shop where the other developers like and use your favorite tools also, and everybody is happy and productive with tools that fit their mind like a glove.

Sunshine, Unicorns, Rainbows, and YourFavStack

Peace! -Tablizer

Comment Re:"flight proven"? hahah (Score 1) 110

Agreed. But besides the metallurgy, SpaceX accepted a bunch of challenges that nobody else wanted to do, to get as far as they have so far.

Nobody else thought fuel densification was worth it. It complicates the launch window because densified fuel has to be unloaded and cooled off if you don't launch in time, and SpaceX had a few technical hiccups to resolve when they started using it. But it gives them more fuel to work with.

We've been able to land rockets on their tail manually since the terrestrial LEM simulator (which almost killed Neil Armstrongr one day) and with computers since DC-X, but SpaceX was the first to try to recover a booster that way.

And the automated barge landing is something nobody ever tried before, but saves a ton of recovery fuel.

No doubt there are a lot of other additions to the list of firsts that were required to get a SpaceX booster recovered.

Comment Re:Vs. Ion Drive [Re:points of interest] (Score 1) 373

Spewing ions is a problem: they're reaction mass and they have to be carried.

But the "power" in ion drives comes from the fast speed of the particles (ions), far quicker than rocket exhaust and near the speed of light. The weight of the material that gets converted into ions is relatively small, no?

Are you saying if a star-ship was built using an ion drive, it would have to carry a large chunk of stuff (relative to the ship) to eventually be ionized on the journey?

If the ship is 10% stuff to be ionized, and the ions spew out at almost the speed of light, then ionizing that chunk should make the ship be going roughly 10% of c when it's done, it seems.

Maybe I'm not considering some relativistic effects and stuck in Newtonian thinking?

Comment Re:Lambda's plug poor OOP language design (Score 1) 346

Sounds like that would break static typing

How so?

Only the syntax of the listener doodad is annoying, the design works well.

If you get used to it, a lot of things "works well". I found it fundamentally unnatural. The info for a given button should be together under a class-like grouping, something like the following pseudo-code:

buttonX = new Button {
  title="Click me";
  method onClick() {
    messageBox.display("Look Mom!");

Comment Vs. Ion Drive [Re:points of interest] (Score 1) 373

If it's so wimpy, why not use ion drives? I thought it was roughly 100x more efficient than ion drives (in tests), and that's why space-travel enthusiasts were excited about it. Your statement seems to say otherwise.

A key difference between EM and ion drives is that ion drives spew radiation to produce thrust while the EM drive allegedly doesn't. While that may be interesting from a physics perspective, it's not a practical issue from a space travel perspective because spewing radiation (ions) is not a significant problem.

In other words, it's not the apparent "something from nothing" aspect that excites travel enthusiasts, but the allegedly efficiency, because moving fast in space requires a hell of a lot of energy.

EMD titillates (or teases) physicists because of the perpetual-motion-machine-like qualities, but it titillates wannabe space-travelers because it's allegedly far more efficient than anything we have, meaning we could approach the speed of light without mountain-sized fuel tanks/reactors.

Comment Re:On its way (Score 3, Interesting) 373

Yes, but given the number of folks who set out to disprove and ended up with thrust they can't explain, we're far from ready to say "no".

If you live in a Newtonian world, you're not going to accept that this could ever work. If you admit to the possibility that momentum could be quantized, you can't rule it out yet.

Comment Re:Prepare to be (Score 1) 373

If it manages to violate conservation of momentum and that stands up to the inevitable scientific pig pile that follows, I'll be impressed.

Conservation of momentum is what makes most of the universe inaccessible to us in practical terms. If it is only a rule of thumb rather than an absolute law, then perhaps more of the universe is within our reach than soberly critical thinking people currently believe. Obviously not with this device, but at least in principle.

But I don't expect any results to survive the pile on. I hope they do, but what I hope and what I expect are two different things.

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