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Comment: I wonder... (Score 1) 75

by SharpFang (#49504043) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

This *might* be an avenue alternative to ion engines for flights that don't stray too far from the Sun. LEO-Moon, Lagrangian Points, inner planets. And it could be combined with ion and rocket propulsion.

You can't store all the propellant at extreme pressures simply because the tank needed to contain these pressures would be extremely heavy. There's a fine balance between weight of the tank and savings on storing pressurized fuel (both energy stored as pressure and more fuel fitting in). We're at "state of art" here and can't push that much farther.

But we can afford a *tiny* extreme-pressure tank, and we have weightless unlimited solar energy at cost of fixed-size, fixed-weight solar panels.

Run the pump with solar power, gradually pressurizing the fuel to quite extreme pressures in the dedicated, tiny, very durable tank. Release it through a narrow nozzle at extreme speeds. Speed it up even more through combustion or electric field of ion propulsion. You're converting solar energy to extra delta-v with no extra fuel usage. You have just the fixed cost of the pump+buffer tank infrastructure and they can be kept really tiny, since we don't try to get a high throughput of the fuel (and have limited energy input anyway), just to increase the propellant stored energy by transforming electricity into pressure.

Comment: Re:Are you retarded? (Score 1) 56

by SharpFang (#49411435) Attached to: How To Make a Bitcoin Address With a TI-89 Calculator

Instead of taking values of keys (which would be a poor seed), take timing of keypresses. If the calculator runs at 1MHz, run a loop that takes 10uS per iteration, and count how many iterations it took between keypresses, modulo 100. No human is capable of timing their keypresses to 1 millisecond with *any* precision, nor correlate the keypresses to any fixed multiple of 10us period, so the sub-millisecond part of timing is entirely random.

So, you're getting about 7 bits of entropy per keypress. Double that for key release. 14 bits per push, d12 is around 3.5 bits of entropy so mash your buttons for a total of 18 keypresses and you have your key.

Comment: Re:The perfect summary of the case: (Score 1) 365

So much for a reasonable discussion. The second your claims are challenged or disproven, you resort to verbal violence. And I'm sure if you had the opportunity, it wouldn't only be verbal. And then you rage when people don't want to treat you seriously.

So typical. Seeing the straw in other's eye...

Comment: Re:The perfect summary of the case: (Score 1) 365

I hope you realize your mindset is what caused the most recent (and ongoing) recession - "the sub-prime mortgage credits" granted to people, who were clearly classified as a high-risk group that would cause severe losses on the average due to failure to pay them - but since they happened to be covered by anti-discrimination laws, the credits had to be granted anyway.

That's when political correctness trumps plain business sense and plain scum can get privleged treatment simply based on their skin color.

The blacks, instead of trying to force more acceptance through laws, should first get to cleaning up their own backyard and simply reduce the reasons that acceptance is so hard to come by: glorification of violence and crime, the "I deserve, you owe me" attitudes, poor ethics, and above all ostracization of these of their society, who grew successful through honest means and education.

Unfortunately, all these anti-social behaviors are ingrained as their "culture" and defended fiercely; they form a self-destructive society and then they resist if the destruction of their society spills out and is fought back.

And these, who broke out of the trap, suffer mistrust and discrimination simply because they are still suspect to be "wolves in sheep skins". And the prevalent belief that they are unable to fail on their own - that all their failures are a result of discrimination - really doesn't help things.

Imagine a situation: There are two black girls that join the college. One studies, works hard and passes all the exams just fine; not brilliantly but well on par with other good students. The other doesn't. She hangs out with the low-life, she choose the life of parties and drinking. When exam time comes, she fails along with fellow white party animals, but unlike them, she submits a complaint that she was discriminated against, and threatens the school with lawsuit. The school yields and grants her the diploma.

The two show up for a job interview. They have the same diplomas. The employer knows about their skill only basing on their diplomas (needs an expert in a field he's a layman in) and has a good clue about practices of extortion of such diplomas. He may choose either of them, or a white graduate who didn't have the leverage of discrimination lawsuit. He has a good business sense, and picks the low-risk white. ...and in this equation the black girl, who worked hard, gets the shortest end of the stick. But who's at fault here? The employer, who puts good business above political correctness? Or maybe these, who allowed the situation where the party animal was able to extort her diploma? Her friends, who gave her the advice "Party on, you're black, you're safe."? Government, that created a law prone to abuse, and as result deterrent to its intended purpose? Her family and surroundings, which reinforced the "they owe me, and it's always their fault" mindset instead of giving her firm work ethics?

It's the "few rotten apples" problem, except the rotten apples are quite numerous and any attempt to "un-rot" them is touted an assault on the black culture.

Comment: List of banned jobs. (Score 2) 331

by SharpFang (#49360879) Attached to: Amazon Requires Non-Compete Agreements.. For Warehouse Workers

"As a current employee of Amazon and looking for a different work, with reference to Non-Compete document# xxx I have signed, I am requesting a comprehensive list of jobs and domains which I'm forbidden to participate in. Currently my job as a janitor of warehouse X leaves me with very little to no knowledge of what products or services are in development, manufacture, marketing, sale , offered or otherwise provided by Amazonof any product or service that competes or is intended to compete with any product or service sold, offered, or otherwise provided by Amazon, and especially the ones it intends any of the above in the future. Since I must know if I'm allowed to perform any of jobs there are openings for, I require this information, so that I don't violate my Non-Compete."

"Please deliver the printed list to my house at [...], as I'm unable to rent a truck to take it home from work."

Comment: Re:The perfect summary of the case: (Score 1) 365

Yes, discrimination against "High-litigation-risk" minorities. The gender/race correlation against said risk makes it appear like gender or race discrimination, but in essence it's just a good business practice to avoid employees that can ruin your business.

The fact feminists thought ruining their employers is a good gender equality promotion tactics... uh.


by SharpFang (#49036387) Attached to: The Technologies That Betrayed Silk Road's Anonymity

Thing with bitcoin is, it's perfectly traceable from wallet to wallet, but the wallet locations are the big unknown. You don't know who owns the wallet until you have access to the physical machine it resides on. So, you can easily *confirm* the transaction between two individuals happened once you know what their wallet IDs are, but if you don't know who the wallet belongs to, you're unable to determine the person from the Bitcoin operations alone.

Comment: Don't connect your alter ego to your real name! (Score 1) 129

by SharpFang (#49036381) Attached to: The Technologies That Betrayed Silk Road's Anonymity

The bottom line is: Don't connect your alter ego to your real name, EVER!

The list of his failures to hide evidence was long. But none of them would have mattered if they didn't learn his name.

First, he posted as 'altoid' advertizing the Silk Road.

Then he posted as 'altoid' seeking help with 'bitcoin service' and soliciting contact with a gmail address which was based on his real name.

That's what got his name on the police's radar. That's why they began to monitor him. Since then it was just a matter of time to slip and reveal true identity. All he had set up would hide him 99.99% of time, making a casual observer or random search to notice his activity pretty much impossible. But a focused observation - being a suspect - could easily correlate things between his two identities. And from then on it was just about catching him red-handed.

Comment: Re:0 hours to 0 hours (Score 1) 244

by SharpFang (#48966825) Attached to: Over the past 10 years, my TV-watching has..

Well, it's hard to tell without a scale. I went from a couple hours per month to zero. So comparing to previous decade decrease (maybe 50h/month) it's only "somewhat"; taking absolutes , it's also "somewhat", by a couple hours. Then taking relative - time spent at the beginning on the period to time spent at the end, it's infinity percent...

Comment: Re:Bless you. (Score 1) 126

by SharpFang (#48964997) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

Deep Space 1 uses NSTAR thrusters with specific impulse of 1,700 to 3,300s and up to 92mN of thrust; they last for just several weeks of operation.

LISA uses FEEP thrusters that produce between 0.001 and 1 mN of thrust at 6,000–10,000s specific impulse, and they are really not intended for travel, but instead for stabilization. (while LISA Pathfinder is merely to test the technology, the planned LISA mission will require three probes positioned in a triangle 5mln km apart with picometre precision.)

Comment: Re:Bless you. (Score 1) 126

by SharpFang (#48921663) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

Fortunately, the Lisa Pathfinder project has already developed ion engines that would be helpful against that. While they generate very minuscule thrust, unsuitable for space travel purposes, they have enormous specific impulse, meaning they can go on for years stabilizing given object against solar wind, gravitational influences and the likes. Several such engines attached to the disk would easily keep it stabilized against solar wind, and another couple on the telescope part would keep it aligned.

Of course you'd need somewhat more powerful jets to turn it around aiming at a different part of the sky, and these would likely need periodic refuelling (note as the disk rotates towards another place in the sky, the telescope part needs to travel a couple thousand kilometers!) but we've got the stabilization covered.

Computers are unreliable, but humans are even more unreliable. Any system which depends on human reliability is unreliable. -- Gilb