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NASA Tests Feasibility of 3D Printing on the Moon and Other Planets

catchblue22 Re:The biggest problem is fluid dynamics. (58 comments)

g is also a unit of acceleration: http://en.wikipedia.org/wiki/G...

I prefer to say that g is gravitational field strength in N/kg. It is equal to the acceleration of a free falling object, but I think it is clearer to think of it as the number of newtons of gravitational force one gets per kg in the field. Of course, 1N/kg is the same as 1m/s^2.

5 days ago
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Orion Capsule Safely Recovered, Complete With 12-Year-Old Computer Guts

catchblue22 Space X Redundant Computing (197 comments)

There are two approaches to radiation tolerant computing. One is to make the processors hardened to radiation. These processors are usually slower, and use an architecture with fewer knowledgable computer programmers. This seems to be the approach on Orion.

In contrast, the Space X Dragon Capsule uses multiple processors operating simultaneously to create a fault tolerant system. To quote:

Dragon uses a "radiation-tolerant" design in the electronic hardware and software that make up its flight computers. The system uses three pairs of computers, each constantly checking on the others, to instantiate a fault-tolerant design. In the event of a radiation upset or soft error, one of the computer pairs will perform a soft reboot.[45] Including the six computers that make up the main flight computers, Dragon employs a total of 18 triple-processor computers.[45]

An advantage of this is that the processors are far faster. There are also many more trained programmers available for these more current architectures. Such systems arguably have similar (or better?) radiation tolerance to the older hardened processors.

about two weeks ago
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IoT Is the Third Big Technology 'Wave' In the Last 50 Years, Says Harvard

catchblue22 Simpsons (196 comments)

I for one welcome our new food cooling overlords.

about three weeks ago
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Multiple Manufacturers Push Hydrogen Fuel Cell Cars, But Can They Catch Tesla?

catchblue22 Re:Where do you fill up? (293 comments)

It is an edge bet against a future where petrofuels are too expensive. With declining oil prices electric cars and hydrogen cars are going to start becoming less attractive just like what happened in the 90s last time this was attempted. Tesla might still sell with their angle on performance. These guys will probably not sell well at all. Plus cost effective ways to produce hydrogen without using petrofuels or natural gas have never actually materialized. One way is high temperature nuclear power plants using thermoelectric water separation but given the current investment into nuclear technologies it is not going to happen. Another way was concentrated solar thermoelectric but that is not cost effective with current methods.

Read my post. Hydrogen as energy transmission is a dead end physics wise. Use the electrical grid and get 90%+ effiency, or use hydrogen and lose most of your energy. Electrolyzing water is, and always will be very inefficient. It will not, cannot reach the efficiency of the grid.

about a month ago
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Multiple Manufacturers Push Hydrogen Fuel Cell Cars, But Can They Catch Tesla?

catchblue22 Re:Where do you fill up? (293 comments)

If one were to buy one of these, how would one proceed to fill up? Would it be a viable transportation option for a road trip?

This is why I think electric vehicles have an advantage...you can put the charging station at your residence. All it needs is a wire. The infrastructure is already there, and can be expanded with relatively little expense. I can imagine charging stations everywhere one parks one's car. We all park our cars at some point, so we will all be able to charge our battery cars enough to make them usable, especially if the charging stations are high capacity.

In addition I think that in terms of space and expense, the potential power output of batteries is far larger than for fuel cells. I picture fuel cells as being finicky and complicated. If I am wrong, please correct me. However I have trouble imagining 800hp output (like the latest Tesla) from a fuel cell. My suspicion is that such a powerful fuel cell would be a Rube Goldberg machine.

Finally, and I think this is the real nail in the coffin for hydrogen as an energy source, is energy efficiency. Creating hydrogen from water, or from whatever other source you have takes a fairly large amount of energy. Let's say we take our hydrogen from water. How much of that input energy will actually make it to the fuel in terms of chemical potential energy? Some of the energy will be put into the O2 bond, which will not be transferred as fuel. Some (most) of the energy will be lost as thermal energy. Only a relatively small amount of the input energy will make it into the fuel. I would be surprised if it was even 20%, and I suspect it is less.

Compare this with gas turbine generators, that can have efficiencies well over 50%. So, you use your natural gas to generate electricity, in which you lose half of your energy already. Now you have a choice: you can use that electrical energy to electrolize water and lose 80% or more of that remaining energy. Or you can use the electrical grid to transfer the electricity directly to the car and lose only about 5% of the energy to the electrical grid.

The laws of thermodynamics are against the use of hydrogen is a fuel. Unless we can find a way of electrolyzing water that has an efficiency equivalent to the electrical grid (more than 90% - and such a process would violate the laws of thermodynamics), hydrogen as a fuel is an obvious dead end. If only the people who ran these companies knew a little bit of physics. I'll take a BSc in Physics any day over an MBA.

about a month ago
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Elon Musk Talks "X-Wing" Fins For Reusable Rockets, Seafaring Spaceport Drones

catchblue22 Re:Advantage of x-wings over normal fins? (96 comments)

Here is a twitter discussion with Musk and Carmak that gives some reasons for using the fins. To quote:

Elon Musk @elonmusk Nov 22

Testing operation of hypersonic grid fins (x-wing config) going on next flight pic.twitter.com/O1tMSIXxsT

Elon Musk @elonmusk Nov 22

Grid fins are stowed on ascent and then deploy on reentry for "x-wing" style control. Each fin moves independently for pitch/yaw/roll.

John Carmack @ID_AA_Carmack Nov 22

@elonmusk Good luck. We had supersonic control inversion issues with actuated fins, went back to little thrusters that worked at all speeds.

Elon MuskVerified account @elonmusk

@ID_AA_Carmack No choice. Entry velocity too high for a precision landing with N2 thrusters alone. Must have aero surfaces for pitch trim.

My suspicion is that there will be a degree of unpredictability for this flight as they refine the control characteristics of these fins. Thus Musk was quoted as saying that the success probability was 50/50 for this landing.

about a month ago
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It's Not Developers Slowing Things Down, It's the Process

catchblue22 Elon Musk on "Process" (186 comments)

This is a quote from Elon Musk on what he thinks about "process":

"I don't believe in process. In fact, when I interview a potential employee and he or she says that 'it's all about the process,' I see that as a bad sign.

"The problem is that at a lot of big companies, process becomes a substitute for thinking. You're encouraged to behave like a little gear in a complex machine. Frankly, it allows you to keep people who aren't that smart, who aren't that creative."

This just about nails it for me.

about a month ago
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Does Watson Have the Answer To Big Blue's Uncertain Future?

catchblue22 Re:Potential Breakthroughs in AI (67 comments)

I forgot to mention...what I describe above is called learning by induction. Which is a form of probabilistic learning.

about a month and a half ago
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Does Watson Have the Answer To Big Blue's Uncertain Future?

catchblue22 Re:Potential Breakthroughs in AI (67 comments)

Our brains are based upon probabilistic computing? Not doubting it since I don't know enough of the "real" neuron details. Just noting it as ironic given how bad we are at assessing risk.

Perhaps I am not using the correct terminology. And I am not an expert...this isn't really my field. But I have seen neural network simulations which, for example recognize handwriting. You show the program many variations on the letter F, and the computer then learns to take symbols that look like the letter F and put them into that group. One can imagine that the brain is made up of many such processes. It certainly sounds like the way that I learned. See a spoon, see mommy using it to feed me, see mommy using it to feed herself. They are all different spoons, but they look similar and they seem to be used to move food from a bowl to a mouth. In a way it isn't that different than taking similar shapes and calling them a particular hand-written letter. It's just that we do this categorization at a myriad of levels on a myriad of objects and eventually of ideas themselves.

I suppose what I think might happen is that instead of building simulations of neural networks, that we will build actual neural networks using some form of electronic system. I don't know what that will look like exactly, but I suspect it is quite possible. After all, nature has already done it.

about a month and a half ago
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Does Watson Have the Answer To Big Blue's Uncertain Future?

catchblue22 Re:Potential Breakthroughs in AI (67 comments)

What is the point of having a nuclear power station for 5 billion dollars emulating a brain if you can make one for something like 200k by inseminating a real WIFE ? And then schooling the offspring etc.

If we can make a human level brain, then we can make something much smarter as well.

about a month and a half ago
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Does Watson Have the Answer To Big Blue's Uncertain Future?

catchblue22 Re:Potential Breakthroughs in AI (67 comments)

For starters, look up how many neurons you can simulate with a single CPU. Then, calculate how many fibers you need for the comms bandwidth.

There is the problem...I think that CPU's are the wrong tool. The problem needs to be re-framed. Perhaps we need synthetic neurons. Then we will need precisely one synthetic neuron to simulate a real one. I know...easier said than done. But we do know the basics of neuron function. Why can't we make a single electronic element that does something very similar?

about a month and a half ago
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Does Watson Have the Answer To Big Blue's Uncertain Future?

catchblue22 Potential Breakthroughs in AI (67 comments)

Neurons can typically fire at a rate of 250Hz. There are about 100 billion neurons in a typical human brain. These neurons are networked in an extremely complicated and changeable parallel network. This network of neurons can be powered for reasonably long time with the energy contained in a bowl of oatmeal. Surely we will at some point be able to create a similar device, and one that doesn't require most of the world's computing power to run.

I suspect the breakthrough will come with a new computing paradigm, one that is based on massive parallelism. Perhaps it will consist of a silicon based device that mimics the network and function of neurons. I suspect it will be based on probabilistic computing, similar to how our own brains work. It will be taught rather than programmed. Perhaps there will be more states than merely 0 and 1.

I think that this is coming, because our brains are already doing it. And with incredible efficiency. Once we saw birds fly, and so we tried to do it ourselves. Eventually we figured it out. I think it will be the same with AI. We will copy nature, learn its principles, and then we will create our own version. And in doing so, I suspect our ideas of what intelligence is will fundamentally change.

about a month and a half ago
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Computer Scientists Say Meme Research Doesn't Threaten Free Speech

catchblue22 The Engineering of Consent (109 comments)

There is a BBC documentary film maker named Adam Curtis who makes some fascinating and disturbing videos about society and control. He has access to the BBC film archives, and uses historical footage extensively. The assertions made are extensively documented and the interviews of powerful people are extremely interesting. I think that this video, The Engineering of Consent, is relevant to this discussion. It is one hour, and quite "stream of consciousness", but worth watching. It is the second episode in a series called The Century of the Self.

From the wikipedia summary:

"This series is about how those in power have used Freud's theories to try and control the dangerous crowd in an age of mass democracy." —Adam Curtis' introduction to the first episode.

Sigmund Freud, the founder of psychoanalysis, changed the perception of the human mind and its workings. The series describes the propaganda that Western governments and corporations have utilized stemming from Freud's theories.

Freud himself and his nephew Edward Bernays, who was the first to use psychological techniques in public relations, are discussed. Freud's daughter Anna Freud, a pioneer of child psychology, is mentioned in the second part, as is one of the main opponents of Freud's theories, Wilhelm Reich, in the third part.

Along these general themes, The Century of the Self asks deeper questions about the roots and methods of modern consumerism, representative democracy, commodification and its implications. It also questions the modern way we see ourselves, the attitudes to fashion and superficiality.

The business and political world uses psychological techniques to read, create and fulfill the desires of the public, to make their products or speeches as pleasing as possible to consumers and citizens. Curtis raises the question of the intentions and roots of this fact. Where once the political process was about engaging people's rational, conscious minds, as well as facilitating their needs as a society, the documentary shows how by employing the tactics of psychoanalysis, politicians appeal to irrational, primitive impulses that have little apparent bearing on issues outside of the narrow self-interest of a consumer population.

about a month and a half ago
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SpaceShipTwo Pilot Named; Branson Vows To 'Move Forward Together'

catchblue22 Flaws in Liquid Solid Engine (112 comments)

I have been reading lately that there has been serious concern about the liquid-solid hybrid engine used in Spaceship 2. In 2007 there was a nitrous oxide explosion that killed three people.

On 26 July 2007, during the early rocket testing phase, an explosion occurred during a propellant flow test at the Mojave Air and Space Port. The test included filling the oxidizer tank with 4,500 kg (10,000 pounds) of nitrous oxide, followed by a 15-second cold flow injector test. Although the tests did not ignite the gas, three employees were killed and three injured, two critically and one seriously, by flying shrapnel.[12]

parabolicarc.com is a pretty good source of information on New Space. Here are some tweets:

Parabolicarc.com @spacecom Oct 31

I had deep concerns over both the new plastic/nitrous oxide engine and so did other sources familiar with the testing. #SpaceShipTwo

The concerns were three fold. One, that it wasn't being tested sufficiently on the ground before it was flown. #SpaceShipTwo

Second: that modifications required to ship to accommodate the new engine introduced additional complexity and failure modes. #SpaceShipTwo

Third, handful of test flights they were doing with new #SpaceShipTwo engine before putting Richard and Sam Branson aboard were insufficient

Let me stress2 things: one, we don't know what happened yet, so I'm not making a snap judgment about what caused the accident #SpaceShipTwo

Second, these concerns about the new engine were not mine alone. Folks much smarter and knowledgble than me were worried. #SpaceShipTwo

I predict you will be hearing a lot more about these concerns and the problems they were having in the days and weeks ahead #SpaceShipTwo

Scaled's Kevin Mickey called the engine change "a minor nuance". He rushed out of the press conference once it was over.

Mickey claimed "minor nuance" engine change thoroughly tested on ground. Tried to ask for details, but presser ended quickly & Mickey left.

Ken Brown was taking photos through the entire incident. Tracked one large piece of debris down to the lakebed. #SpaceShipTwo

I heard Ken say, "They're in trouble." And then "They're tumbling. Ken's pictures will be very crucial to understanding it. #SpaceShipTwo

Just talked to Ken Brown. Pictures show Engine fired fine, then there's a white plume. He thinks the nitrous oxide tank blew. #SpaceShipTwo

I am a huge supporter of commercial space, most especially Space X. But I think that accidents like this give the whole sector a bad name. Virgin Galactic/SC have been building this ship for 10 years, and they still don't have a viable engine. That is not a good sign.

Contrast that with Space X, which in about the same amount of time has built the Falcon 9, which has a string of 13 straight successes (touch wood). It seems to me that not all space companies are created equal.

about 2 months ago
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Antares Rocket Explodes On Launch

catchblue22 Re:Elon Musk Called it Two Years Ago (443 comments)

The engines were probably fine, chances are it's something to do with the fuel delivery system that caused the explosion.

The Russians built good engines, and they built a lot of them because they anticipated needing many to get to the moon. Rather than a few big engines like the Saturn V they were using 30 odd smaller ones to do the same job. They had some problems but eventually got it working, just because they abandoned the idea of manned moon missions.

My guess is that it was a turbo-pump that failed. Those are a part of this Soviet engine, and were also likely made in the 1960's.

about 2 months ago
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Antares Rocket Explodes On Launch

catchblue22 Elon Musk Called it Two Years Ago (443 comments)

Elon Musk called it two years ago in this interview.

Musk: The results are pretty crazy. One of our competitors, Orbital Sciences, has a contract to resupply the International Space Station, and their rocket honestly sounds like the punch line to a joke. It uses Russian rocket engines that were made in the ’60s. I don’t mean their design is from the ’60s—I mean they start with engines that were literally made in the ’60s and, like, packed away in Siberia somewhere.

about 2 months ago
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Antares Rocket Explodes On Launch

catchblue22 Re:All very sad (443 comments)

NASA spent many years developing processes and vehicles that, initially, had a very high failure rate. Today we are conditioned to expect that these launches will go off safely, but do we need to give the private sector 20 years or so to sort itself out before we start allowing people to fly in their rockets?

Almost all the US space program is ALREADY private. The dominant US launch platform is United Launch Alliance, which was created by a merger of Lockheed Martin and Boeing when the US tried to bring in competitive bidding for Air Force launches. Their merger allowed them to become the sole bidder on most launches, allowing them to continue to receive their cushy "cost plus" bids. These "cost plus" bids allow them to pretty much charge whatever they want for costs, and then receive on top a guaranteed profit margin. There is no incentive for efficiency. In fact, ULA has almost no international customers because their costs are more than double their competitor's prices. They grow fat at the teet of the US Air Force.

Space X is a relative newcomer, but since its first generation rocket (Falcon 1) had three failures, the last of which was caused by a timing error in stage separation, it has had a nearly perfect launch record. The Falcon 9 rocket has never had a significant failure (ie. one that prevented orbit of the primary payload). Touch wood. Their rockets have been designed in house with the eventual goal of re-use. Their rocket engines are designed to be simple and failure resistant. And their rockets have nine engines, so that even if one fails the flight can continue. I wouldn't write off competition yet.

about 2 months ago
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Antares Rocket Explodes On Launch

catchblue22 Re:Horrible track record (443 comments)

I seem to remember a SpaceX rocket accidentally self destructing recently. And people have died serving NASA missions. Tell me who has this illusive awesome track record you are looking for?

It was a test vehicle that self-destructed, and not a full rocket. The test vehicle did not have all of the redundancies of the production rocket. A single sensor failure stopped the rocket. In the real rocket, there are multiple redundant sensors from which the control systems constantly poll...if one goes, the computer ignores it in favor of the other working sensors.

about 2 months ago
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We Are All Confident Idiots

catchblue22 Obligatory Socrates Quote (306 comments)

When I left him, I reasoned thus with myself: I am wiser than this man, for neither of us appears to know anything great and good; but he fancies he knows something, although he knows nothing; whereas I, as I do not know anything, so I do not fancy I do. In this trifling particular, then, I appear to be wiser than he, because I do not fancy I know what I do not know.

From Socrates, The Apology (399 B.C. or so)

Everything old is new again.

about 2 months ago
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We Are All Confident Idiots

catchblue22 Re:Left one out (306 comments)

The problem here is that Prof. Dunning's principle could apply to anybody, including college professors. So how does he know he is correct? --- "Science is the belief in the ignorance of experts." -- Richard Feynman

Are you sure about that?

about 2 months ago

Submissions

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Will ultrasound-on-a-chip make medical imaging so cheap that anyone can do it?

catchblue22 catchblue22 writes  |  about a month and a half ago

catchblue22 (1004569) writes "MIT Technology Review has an article describing a potentially groundbreaking invention:

A scanner the size of an iPhone that you could hold up to a person’s chest and see a vivid, moving, 3-D image of what’s inside is being developed by entrepreneur Jonathan Rothberg.

Rothberg says he has raised $100 million to create a medical imaging device that’s nearly “as cheap as a stethoscope” and will “make doctors 100 times as effective.” The technology, which according to patent documents relies on a new kind of ultrasound chip, could eventually lead to new ways to destroy cancer cells with heat, or deliver information to brain cells.

"
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Microsoft's Quantum Mechanics

catchblue22 catchblue22 writes  |  about 2 months ago

catchblue22 (1004569) writes "MIT Technology Review has an excellent article summarizing the current state of quantum computing. It focuses on the efforts of Microsoft and Alcatel-Lucent's Bell Labs to build stable qubits over the past few years.

In 2012, physicists in the Netherlands announced a discovery in particle physics that started chatter about a Nobel Prize. Inside a tiny rod of semiconductor crystal chilled cooler than outer space, they had caught the first glimpse of a strange particle called the Majorana fermion, finally confirming a prediction made in 1937. It was an advance seemingly unrelated to the challenges of selling office productivity software or competing with Amazon in cloud computing, but Craig Mundie, then heading Microsoft’s technology and research strategy, was delighted. The abstruse discovery—partly underwritten by Microsoft—was crucial to a project at the company aimed at making it possible to build immensely powerful computers that crunch data using quantum physics. “It was a pivotal moment,” says Mundie. “This research was guiding us toward a way of realizing one of these systems.”

"
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The Gods Strike Back: Wall Street's Risky Hubris

catchblue22 catchblue22 writes  |  more than 4 years ago

catchblue22 (1004569) writes "The Economist has an interesting essay that gives some perspective on our economic situation. From the article,

THE revolutionary idea that defines the boundary between modern times and the past is the mastery of risk: the notion that the future is more than a whim of the gods and that men and women are not passive before nature. So wrote Peter Bernstein in his seminal history of risk,"Against the Gods".

Wall Street quants have claimed over the past decade that they had the ability to quantify financial risk down to several decimal places. The Great Recession has shown their claims to be absurd. Wall Street's supposed mastery of risk allowed financial institutions to package risky loans as derivatives that ostensibly had definite and identifiable risk profiles. Our recent financial collapse shows the limits of our beautiful and elegant mathematical models of the economy."
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