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Comment Re:Send in the drones! (Score 4, Insightful) 848

Im not 100% clear why we wouldnt want to get involved here, if ever there were a time to get involved.

Ukraine disarmed itself in 2006 at our urging, with the understanding that we would come to their aid if ever it were needed. At the same time, having a superpower like Russia going into full imperialism mode is good for noone but Russia. A tepid response like the one theyve been given will only encourage further aggression.

Assuming that you are implying American boots/bombs on the ground in the Ukraine, are you crazy? I mean seriously. Are you? There is in my opinion a dangerous detachment from reality in some circles of American political discussion about confronting Russia. Perhaps you may feel my language is inflamatory. But I get kind of disturbed when so many people, including those in power, put forward actions which would likely lead to thermonuclear war.

Looking back at history, there has never been a shooting war between the Soviet Union and the US. Never. The Cold War? It was always fought between proxies of the great powers. We would sell arms to pro-US or anti-Soviet interests (like in 1980's Afghanistan), or we would directly confront pro-Soviet interests (like in Vietnam). We came close to a shooting war with the Soviets more than once (the Bay of Pigs in Cuba). But such a war never happened, because those in power knew that such a war would inevitably decay into a thermonuclear war that would likely end western civilization with the press of a button.

The proper response to this is to strengthen military forces in new NATO member states surrounding Russia, including US boots on the ground. This will make a clear line that Russia knows it cannot cross without provoking all-out war. Unfortunately Ukraine is not part of NATO. We might be able to sell arms to Ukraine, but there are risks and limitations to this. What must be made clear to Russia is that if it enters Ukraine, it will face profound economic isolation. If it goes further it must be clear that it will result in WWIII. Thus we end in a stalemate. Not unlike the Cold War.

Comment Re: Public cynicism about fusion (Score 1) 147

Here is the PhD thesis of Thomas J. McGuire who is designing the compact fusion device mentioned in the parent comment. This 2007 thesis argues for the need to build compact fusion devices and surveys some options with their strengths and flaws. I don't think it describes in detail the high beta reactor he is currently designing at Lockheed Martin. Still, it shows the idea of him designing this reactor is plausible.

Comment Re: Public cynicism about fusion (Score 4, Interesting) 147

The Skunkworks high beta fusion reactor seems very interesting. 100MW reactor the size of a semi trailer and the complexity of a jet engine. Uses radio waves to heat the plasma (like a microwave oven). Confines plasma in a cylinder as opposed to a torus. In a tokamak reactor the confining magnetic field is created by the motion of the plasma. Thus the strength of the field decreases further from the plasma, creating an inherent instability. This creates a negative stability feedback because if the tokamak plasma expands the confining field gets weaker. I believe this is one of the reasons tokamaks need to be so huge to function.

The high beta reactor has a confining field that increases in strength as you move farther from the plasma, making confinement inherently stable. The machine was designed by Dr. Thomas McGuire who did his PhD thesis on fusors at MIT. It may be possible to build a full reactor by as soon as 2017 for a cost measured in millions, NOT billions.

Comment Re:Makers! (Score 5, Informative) 108

What "rocket engine" is 3D printed?

The nozzle for the Superdraco engine is 3d printed. The alloy is too hard to machine, so 3D printing is the only practical way of manufacturing them. It will be the landing thruster for the propulsive landing Dragonfly crew vehicle. It will land with the accuracy of a helicopter. Here is a video of it being cycled through its various thrust levels. Very cool.

Comment Problems with SLS (Score 3, Informative) 53

Aside from the horrific cost of the SLS (18 billion dollars) it is worth considering the fundamental flaws of it. If you use it to launch astronauts with the Orion spacecraft, you are using somewhere around a quarter of the SLS's lift capacity. If you want to use it to send things to Mars, you will need to add another stage, which is non-trivial. Overall, this seems like a giant corporate welfare program for NASA's contractors.

Comment Watch out for ULA Propaganda (Score 5, Interesting) 393

I have posted before that there is evidence that ULA has initiated a propaganda campaign against Space X. From what I have read, Shockey Scofield Solutions, which is a PR firm hired by ULA is tightly linked with congressional lobbyist culture...they know how to pull particular strings in Washington. This seems to have their fingerprints all over it.

We should really be aware of the reason why ULA was formed in the first place. A few years ago the government decided to bring competition into launch procurement, by creating a bidding process. The dominant/only American players, Boeing and Lockheed responded by merging their launch products into the United Launch Alliance so that in almost all cases there would be only one bidder for American launches. This resulted in an increase in launch costs.

Enter SpaceX, which looks to be a real competitor. ULA can't absorb Space X, so they seem to be doing everything they can to sabotage them instead. From proposing financial rules on bidding companies that are biased against smaller players, to focussing on trivial "anomolies" that put uncertainty in the (simple) minds of Congressional lawmakers, to floating fanciful speculative stories about future vaporware "Space Planes" that will leapfrog SpaceX's cheaper launch platforms, to calling Elon Musk a corporate welfare bum (as if ULA wasn't the queen of queens of welfare queens).

The simple fact is that Space X has taken older proven technology and molded it into what promises to be a robust and reliable launch platform. ULA knows this, and the only thing they know how to do is to make this a gutter fight. They are despicable.

Biotech

Injecting Liquid Metal Into Blood Vessels Could Help Kill Tumors 111

KentuckyFC (1144503) writes One of the most interesting emerging treatments for certain types of cancer aims to starve the tumor to death. The strategy involves destroying or blocking the blood vessels that supply a tumor with oxygen and nutrients. Without its lifeblood, the unwanted growth shrivels up and dies. This can be done by physically blocking the vessels with blood clots, gels, balloons, glue, nanoparticles and so on. However, these techniques have never been entirely successful because the blockages can be washed away by the blood flow and the materials do not always fill blood vessels entirely, allowing blood to flow round them. Now Chinese researchers say they've solved the problem by filling blood vessels with an indium-gallium alloy that is liquid at body temperature. They've tested the idea in the lab on mice and rabbits. Their experiments show that the alloy is relatively benign but really does fill the vessels, blocks the blood flow entirely and starves the surrounding tissue of oxygen and nutrients. The team has also identified some problems such as the possibility of blobs of metal being washed into the heart and lungs. Nevertheless, they say their approach is a promising injectable tumor treatment.

Comment Re:What about a coal powered Tesla? (Score 1) 122

Don't forget the processing and distribution costs associated with liquid fuels... including the ethanol.

Yes. I think my calculations are conservative. Especially if we are relying on fuel from the tar sands, which are MASSIVELY inefficient in terms of CO2 emissions. They have to melt the tar in order to separate from the sand and refine it. They use natural gas and a large amount of fresh water. Think about that water, Californians. Now much of that wonderful fresh water is languishing in huge pools, mixed with a toxic slew of organic chemicals and heavy metals.

The tar sands are madness. When I think of Alberta tar sands, I think of Mordor.

Comment What about a coal powered Tesla? (Score 5, Insightful) 122

So... not to stir up a hornets nest... but everyones aware that electric cars produce more pollution than gas right?

Let's look at some facts here. First off, the efficiency of a thermal power plant is somewhere around 33% to 48%, at least according to wikipedia. Let's split the difference and say 41% for a thermal plant. The typical thermal efficiency of a a gasoline engine is about 18% to 20%. Let's split the difference and say 19%. Thus, a thermal power plant is more than twice as efficient as a gasoline engine in terms of changing chemical potential energy to useful output.

But there are some caveats. Firstly, the electricity needs to be transmitted. High voltage power lines are extremely efficient, about 94% according to this article. That means that the chemical energy (lets assume from coal) reaching the charging station is 41% x 94% = 38.5%. And then there is the charging process. According to this article, the charge efficiency of a Li-Ion battery is about 97%, which makes sense to me, as batteries usually don't run too hot. The charging devices however probably are responsible for some loss. Let's assume they are 80% efficient. That gives us 38.5% x 80.0% x 97% = 30%. Thus, according to this, 30% of the coal chemical potential energy makes it to the engine.

But what about engine efficiency? Well electric motors run very cool, and have very high efficiencies, typically around 90%. I wouldn't be surprised if Tesla's motor is better. This means that if a coal power plant powered a Tesla, 30% x 90% = 27% of the energy would reach the wheels of the car, compared with a gasoline powered car, where 19% of the gasoline's potential energy comes out of the engine, never mind the losses in the transmission lines. Thus, a coal powered Tesla is 40% more energy efficient than a gasoline powered car.

However, there is one problem. Generating energy by coal produces more CO2 than generating it by gasoline. According to this article, coal generates about 215 pounds CO2 per btu of energy, while gasoline generates 157 pounds CO2 per btu. However, even with this, by my calculations, an equivalent gas powered car still emits 3.8% more CO2 than our coal powered Tesla.

Elon Musk made this claim in an interview, that even if a coal power plant generates the electricity, a Tesla still emits less CO2. My referenced back of a napkin calculations above support this assertion.

Comment Anti-SpaceX Propaganda Campaign (Score 3, Informative) 114

As this article indicates, United Launch Alliance, the principle competitor to SpaceX has hired Shockey Scofield Solutions to initiate a propaganda campaign against SpaceX. You can see ULA listed as a client in the website listed above. The campaign is indirectly mentioned in the following very informative article, just past the halfway point in the article. You will also notice another client to Shockey Scofield Solutions as Koch Industries, which is a company notorious for its deceptive propaganda campaigns against action on global warming.

Given this fact, I would tend to suspect many of the anti SpaceX comments as being part of an astroturfing campaign. To be honest, I really don't understand why an actual thinking person would have any problem with SpaceX. They build reliable rockets quickly and cheaply. What on Earth is the problem with that?

Comment Re:How Many Employees are Required? (Score 2) 272

Actually Windows XP was based on the Windows NT architecture. Windows 95, was based on the DOS architecture.

Windows 95 was decades ago, it wasn't up to modern standards but it was certainly better than Mac OS 7 or Linux 1.0. It's time to move on.

OSX in fact precedes windows 95, let alone Windows NT. That's right, because the best parts of OSX originate in NeXT, which was sold as a product in 1988, six years or more before windows 95. And the reason why NeXT/OSX were so great so early was because they were based on the decades old Unix architecture. And don't talk about Mac OS 7. It was dead end garbage. Only the most superficial structures from Mac OS made it into OSX.

Comment How Many Employees are Required? (Score 1) 272

Consider the history of major software projects, and how many employees were required. BSD unix was a university project, developed by faculty and students. Linux was developed initially by one person, and then a relatively small team. NeXT was developed by a fairly small team over a relatively small amount of time. Mac OSX was basically the NeXT system ported over to the Mac platform; at the time, Apple had about a tenth of the employees of Microsoft, and was under significant financial stress. iOS and the iPhone were developed by a very small team within Apple (20+ employees if I am not mistaken). The interesting thing is that all of these systems have displayed remarkable stability and security. This likely has something to do with the fact that these OS's are all unix derived. However I find it interesting that such excellent products did not require large numbers of programmers to develop.

Contrast the above with the offerings of Microsoft over recent years. Most especially consider Vista, Win7 and Win8. During the development of these systems, Microsoft had a huge number of excellent programmers. Why did it take them so long to develop these operating system versions? Why has MS had such difficulty porting over to different processor architectures, such as ARM? Apple has had no such difficulty, porting OSX/ iOS from PowerPC to Intel to ARM. I believe that a fundamental cause of the difficulties that MS has experience with Windows lies in the early stages of operating system development. Whereas the systems based on Unix were built on a solid and proven foundation from their earliest versions, Microsoft has from a very early stage shown a tendency to build its own early versions on its own unproven architecture, with the intention of fixing the significant problems later.

Early versions of Windows 95 had very limited networking protocols, that were intended for home networking only. Wide area networking was added as an afterthought. Contrast this with unix variants, which are based on an architecture that grew up in an environment of university main-frames with hostile tinkering computer science students vying to break the system.

Anyone who worked with Windows 95 can attest to the buggy mess that it was. I supported people using it, and I remember the problems. User says, "my system crashed so I rebooted it. It still didn't work so I rebooted it again. It still didn't solve the problem." Tech guy responds, "well there's your problem. Tap the computer twice, pray to the god of your choice, and reboot it a third time, and it should be fixed."

Windows XP, Vista, 7, and 8 all originate from that same architecture, right down to the fact that they all share the engineering disaster that is "the registry". How can Windows ever be truly solid when it is built on such a bad foundation. I believe that the reason why Microsoft has had such difficulty building a solid OS stems from this weak foundation. It explains why it took MS many years and a staff 10x that of Apple to build the marvel that was Vista. As Mythbusters showed, it is possible to polish a turd. However it takes a lot of effort. And in the end, you still only finish with a polished turd.

Comment Re: Catching the big choices (Score 2) 710

Not to mention that I cook more at home than average. In my place, cooking is responsible for the largest part of the electric bill. Cooking at home puts me slightly above average on electricity usage, even if I have all led/fluorescent lights. I don't even use my electric heat 95% of the time.

Comment Catching the big choices (Score 4, Insightful) 710

I am not sure this study captures the some of the bigger decisions made to conserve energy. For instance, here is what I have done: I live in a condo that has a high walk score, so I don't have to drive much. We are close to transit and we use it. I purchased a Prius, which gets 60mpg. Given that and the fact that we barely drive, our monthly gas bill is about $50. One tank per month. I don't eat much meat. This substantially reduces the carbon emissions from the production chain of my food. However, according to this study, I am being remiss if my electricity bill isn't lower than my neighbours' bills. The study is flawed. My overall carbon emissions are way lower than average but this study would overlook me.

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