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How Japan Plans To Build Orbital Solar Power Stations

mangu Re:Satellites have eclipses (230 comments)

Wut? Unless that set period is so short it needs building additional facilities, the price for repeated launches will only go down, never up.

Imagine the time period is the same you need for building a 1 GW power plant using any traditional technology. That will be a few years. Meaning you could do a launch every couple of days and complete a thousand launches in the same period. You could do that from a single launchpad.

The reason why they don't do launches day after day right now is because there is no demand for so many launches, but they certainly could adapt the procedures for that.

about 7 months ago
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How Japan Plans To Build Orbital Solar Power Stations

mangu Re:Satellites have eclipses (230 comments)

The cost of sending 10 metric tons to LEO and about 5 metric tons to GEO is claimed by SpaceX to be slightly under $60 million USD

For a single launch. Ask them about their discount for a thousand.

about 7 months ago
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How Japan Plans To Build Orbital Solar Power Stations

mangu Satellites have eclipses (230 comments)

In the geostationary orbits there are two periods each year, around March and September, when the satellites are eclipsed by the earth. That's why geostationary satellites need batteries, which are among the heaviest parts of a satellite. And, unfortunately for the power generation idea, these eclipses occur at night for a satellite located above the point it's beaming at.

As for the cost, launching 10,000 tons could be done for something like $50 billion or so. We are talking about a thousand launches, so it would pay to build your own rockets, which would bring the price down.

The exact costs of the launchers today is a closely guarded trade secret, but it's certainly less than the price you pay. Certainly, with a private company with development costs amortized over a thousand units, they could bring the launch costs to a less prohibitive level.

about 7 months ago
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Blood of World's Oldest Woman Hints At Limits of Life

mangu Re:Bank them (333 comments)

trying to force a 100 year old body to keep it's heart beating

Hint: by the time science discovers more about the mechanism of aging, it won't be a 100 year old body anymore.

All of her white blood cells were being produced by just two stem cells. Imagine if they could replicate stem cells indefinitely, her body would become 20 years old forever, not 100.

about 7 months ago
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Our Education System Is Failing IT

mangu Re:Philosophy is the opposite of mathematics (306 comments)

I took a philosophy course and an engineering degree. After working 30 years in engineering, I can tell for sure that philosophy is NOT the answer to engineering problems.

If too many people working on IT are under trained, you may blame the education system for failing to provide them with enough training in that field, not for failing to provide them education in totally unrelated fields.

about 7 months ago
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Our Education System Is Failing IT

mangu Philosophy is the opposite of mathematics (306 comments)

Philosophy to come up with the right argument and psychology to make it stick

Unfortunately, philosophy is very far from coming with the right argument. I took a philosophy course in college, to "broaden" my outlook, and it had the exact opposite effect. Read any text by a philosopher, and in the end you'll get to the conclusion that perhaps there could be one or two good ideas there, if it had been written in a hundred words instead of a hundred pages. That's why sometimes a philosopher seems so smart to the uninitiated, they have read only the aphorisms and quotations, they have never had to pore through a full book written by a philosopher.

IT is a field for many different specialists. In the most common forms, what is needed is an expertise in human interfaces, we need graphics designers to create the screens and writers to create the documentation. In that sense, yes, it's all about expertise in the humanities. The vast majority of IT work in development is about personal and corporate software, of which data input and presentation is the bulk of the thing.

Logic and mathematics, although it's behind every software, is a very small part of the development job. However, it cannot be totally disregarded, because it's an essential part.

There's the dilemma we face. We cannot just exempt people working in IT from training in the essential parts most of them will never use, because we never know when those skills will be needed.

Those programmers who say "I've never used a differential equation" are people who slept through their calculus courses and cheated at the exams. If you are simulating pitching a ball or you are calculating the profits from an investment fund you are using differential equations, and you should know how to do the job. Unless you work for a big company, you cannot be assured that the only things you'll ever need to do is drawing screens and writing manuals.

about 7 months ago
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Experts Say Hitching a Ride In an Airliner's Wheel Well Is Not a Good Idea

mangu Terrorists, not tourists (239 comments)

I guess the memo had a misspelling. The wheel wells seem to be a good place for terrorists, not for tourists.

If someone can sneak up to the plane and climb in, it should be equally easy to put a bomb there. If a 16-year-old can find a way to squeeze into that space, it wouldn't be too difficult to fit in a couple hundred pounds of explosives.

about 7 months ago
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Australia May 'Pause' Trades To Tackle High-Frequency Trading

mangu ANY delay destabilizes the system (342 comments)

If you need to sell some stock or commodity within a second of buying it, then something is wrong

Oh, yeah? Then, please, tell me in your infinite wisdom how long I should wait? Ten years? Twenty?

The fact is that ANY delay in a feedback system tends to destabilize it. In mechanical systems this is called "backlash" and there is extensive research on how to eliminate it and cope with the problems it causes. Anyone who proposes to artificially introduce backlash in a feedback system know nothing about what he is talking about.

In a market it would be trivially easy to manipulate prices if an artificial delay were involved, especially for the bigger traders. Put a buy order for a million shares and watch the prices rise, then sell at the higher price that would result a half second later. The same principle would work no matter how long the delay is.

Markets work so well because there is negative feedback in many different loops all over the economy. Some of these loops have shorter response times, other are slower to respond. If you invent an artificial delay that overlaps everything, this creates a well defined eignevalue that anyone with the proper technical knowledge could exploit.

about 8 months ago
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Australia May 'Pause' Trades To Tackle High-Frequency Trading

mangu Tax == Arbitrage (342 comments)

Imposing a tax only means the profit threshold is raised. That creates the market distortion called "arbitrage", where the relative costs between different transactions are not symmetric.

A .01% tax per transaction would mean that for me, a small trader, there would be a net loss unless my own profit per trade is lower than .01%. For a bigger trader, the cost per trade is lower, therefore they would gain and advantage over us, the smaller guys.

The true solution? Let it be, do not change anything.

Apart from some guys who get a lot of profit selling books claiming HFT is bad, no one actually makes very much on HFT. The margins are very low, extremely low, so you need to invest a lot of capital to get any profit from it.

Getting a small profit from economy of scale is something that hurts no one, it happens in every sector of the economy. As a small investor, I have an indirect gain from the higher liquidity when the big investors go into HFT.

The economy is not a zero-sum game, there are situations where everyone profits and situations where everyone loses. With HFT everyone gains, with taxes everyone loses.

about 8 months ago
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Book Review: How I Discovered World War II's Greatest Spy

mangu Re:Greatest, but maybe not the most damaging (102 comments)

The US didn't need to use the bomb again, the mere knowledge that it existed was enough.

Anyhow, it was several years until the Soviets got their own bomb, and even longer until they had some way to deliver them. Until the mid-1950s at least the Soviets had no bomber planes or missiles capable of dropping atom bombs on the USA.

about 8 months ago
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NASA Wants To Go To Europa

mangu History vs Pre-history (216 comments)

That's how we define what is called "history". If it happened before writing existed, it's not part of history.

Although, to be fair, Catholic missionaries destroyed a lot of written records from pre-Columbian America. They literally deleted Inca history.

about 9 months ago
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Dyson Invests £5 Million To Create 'Intelligent Domestic Robots'

mangu Re:I'm not covinced by Dyson (125 comments)

And don't someone come up with the BS about everyone will sit around in blissful nirvana writing poetry or music or coding or go kayaking all day.

No, of course not. They will sit around and watch TV.

How many people have the ability and the inclination to write poetry or music or code anyhow?

about 9 months ago
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Google Buys UK AI Startup Deep Mind

mangu Voice needs context (113 comments)

Voice interface is one of the hardest things to implement well in AI because there are so many sentences that sound similar, understanding depends so much on context.

Without understanding the context of the conversation, a voice interface will not be able to know if you are talking about sodas or sawdust, robots or row boats, new displays or nudist plays.

about 10 months ago
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Ask Slashdot: It's 2014 -- Which New Technologies Should I Learn?

mangu C object inheritance (387 comments)

In C you just cannot use inheritance in any useful way

struct coord
{
  int x, y;
}
 
struct pixel
{
  struct coord loc;
  int r, g, b;
}

about 10 months ago
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How Quickly Will the Latest Arms Race Accelerate?

mangu Bye bye, aircraft carriers (197 comments)

work on space exploration, fusion power, renewable food production,

You know what's even worse than working on developing weapon systems? Working on 90 years old weapon systems.

Aircraft carriers were state of the art during WWII, today they are as obsolete as the USS Arizona was in 1941.

What's the point is spending hundreds of billions of dollars in building sitting ducks that can be taken out by a single hypersonic missile?

about 10 months ago
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The Internet's Network Efficiencies Are Destroying the Middle Class

mangu Re:Here We Go Again (674 comments)

your own personal information that is being bundled up and sold off.

I repeat, there is no need to "monetize" everything.

Does that personal information have any monetary value to you? Can you sell it? Does someone using it take anything away from you? If not, then you are losing nothing while you get to use the services of a site without having to pay for it.

All that information does is to enable someone to send you advertisements that might interest you. If it doesn't interest you, too bad, but it's no worse than all the junk mail you have been receiving for so many years.

Anyhow, if you do not like the way it is, no one is forcing you to use any of those sites. It's not like the government taking taxes away from your pockets.

about a year ago
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The Internet's Network Efficiencies Are Destroying the Middle Class

mangu Re:Here We Go Again (674 comments)

How did this half-wit get published by the NY times?

Hint: they also publish the bullshit that Paul Krugman writes.

It's easy to say that internet companies only employs X people, while forgetting that they do not charge users for whatever they provide.

I, for one, think the greatest economic advantage is when we are able to get things for free. There's no need to "monetize" everything.

about a year ago
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Researchers: Global Risk of Supervolcano Eruption Greater Than Previously Though

mangu Meanwhile, in North Carolina... (325 comments)

Your failure to predict it will still get you arrested in Italy.

But if you predict it you will be arrested in North Carolina.

about a year ago
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Nvidia Announces 192-Core Tegra K1 Chips, Bets On Android

mangu Re:"Android most important platform for gaming" (128 comments)

There will be plenty of people who prefer casual games on a phone screen, there will be plenty who prefer high-resolution fancy graphics displayed on their big TV with a control system more flexible than a touch screen

The problem with consoles right now is that any argument you can make for consoles vs. tablets you can also make for PC gaming vs. consoles, and any argument you can make for consoles vs. PCs you can also make for tablets vs. consoles.

Consoles are in an ever shrinking gap between tablets and PCs, I don't think their market has very much space to grow.

about a year ago
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Stellar Trio Could Put Einstein's Theory of Gravity To the Test

mangu Re:Will be interesting ... (106 comments)

And how do you know if your equations are correct?

That's the whole point raised by TFA. You know your equations are correct if the results of the simulation agrees with the results of the observation.

This system offers an unprecedented way to check how much does model general relativity fit the actual universe.

It's all in TFA, but I suppose reading it breaks the slashdot rules. Since we have three stars that are much more massive than any other three body system observed before, we can make measurements of the effects of gravitation with more precision, because the effects of those three stars on each other are so much bigger than the perturbations from other masses.

about a year ago

Submissions

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Lawsuit accuses Apple of foxing worker pay

mangu mangu writes  |  more than 3 years ago

mangu (126918) writes "Siddarth Hariharan, a former software engineer for Lucasfilm, filed a class action suit in California accusing a number of companies of antitrust violations and unfair competition. At the core of the suit is a series of agreements among the corporations, with Apple in the central role, to limit the competition among them for technology workers. Besides Apple, the companies mentioned are Pixar, Lucasfilm, Adobe, Google, Intel, and Intuit. Basically, the interconnected agreements consisted in not to “cold call” one another’s employees. Considering that switching jobs is one of the few opportunities a technology worker has to get a significant pay raise these agreements imposed strong limits on career evolution."
Link to Original Source
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Iran to 'remove fuel' from Bushehr nuclear plant

mangu mangu writes  |  more than 3 years ago

mangu (126918) writes "Iran said on Saturday it is removing the fuel from the reactor of a Russian-built nuclear power plant, a move seen as a big blow to its controversial nuclear program. The plant was first launched by the shah using contractors from Siemens. It was shelved after the Islamic revolution and it lay unfinished through the 1980s. In the early 1990s, Iran sought help for the project after being turned away by Siemens over nuclear proliferation concerns. In 1994, Russia agreed to complete the plant and provide the fuel, with the supply deal committing Iran to returning the spent fuel. The plant has faced hiccups even after its physical launch, with officials blaming the delays in generating electricity on a range of factors, including Bushehr's "severe weather." But they deny it was hit by the malicious Stuxent computer worm which struck industrial computers in Iran, although they acknowledge that the personal computers of some personnel at Bushehr were infected with it."
Link to Original Source
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Could a meteorite have hit Flight 447?

mangu mangu writes  |  more than 5 years ago

mangu (126918) writes "Air France flight 447 went down in the Atlantic Ocean last sunday with 228 people on board. The cause of the accident is still a mystery. A http://www.straitstimes.com/Breaking+News/World/Story/STIStory_385883.html>Spanish pilot 2000 km away saw 'an intense flash of white light' in the area where Air France Flight 447 was lost, the El Mundo newspaper said on Thursday. Could the unlucky plane flying from Rio de Janeiro to Paris have been hit by a meteorite, an event that has a probability of happening once every 59000 to 77000 years?"
Link to Original Source
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mangu mangu writes  |  more than 7 years ago

mangu writes "Ex-MPAA president Jack Valenti died today at the age of 85.

"Jack was a showman, a gentleman, an orator and a passionate champion of this country, its movies and the enduring freedoms that made both so important to this world," his successor, Dan Glickman, said in a written statement announcing Valenti's death. "He also embodied the theatricality of our industry with his conviction, quick wit and boundless energy. In a very real sense, he was the ultimate leading man."
"
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mangu mangu writes  |  more than 8 years ago

mangu writes "The Brazilian government Public Ministry, that is, more or less equivalent to the Attorney General's office in the USA, is threatening to sue Google unless they get the identities of people who have created Orkut communities on subjects such as racism, neonazism, homophobia, abuse against animals, and religious intolerance. So far Google has refused to supply data about the identity of the persons involved, but they have agreed to remove the infringing Orkut communities. Despite the nominal protection on freedom of expression in the Brazilian constitution, the legislation allows many exceptions that effectively limit the subjects which may be discussed publicly in Brazil. Publishing any text that incite "apology of crime", "racial prejudice", or "religious intolerance" is a felony according to Brazilian federal law."

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