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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.

Comment Re:Warp Drive (Score 1) 564

Neural networks was one of the worst misdirection in the history of AI. These was a lot of wasted effort on that idea.

Have you seen what neural networks are doing recently? I think you will find that the course on machine learning I linked to is primarily about neural networks. Your opinions are asserted very strongly but you give me no reason to think you know much about the field other than your swagger.

Comment Re:Warp Drive (Score 1) 564

I see no evidence of any programming that "learns" or is the slightest bit adaptive.

Ever heard of neural networks? Machine learning? Here is a course given Andrew Ng at Stanford. Watch the intro video, and you will see, amongst other things an autonomous helicopter that was taught, not programmed but taught to do an inverted takeoff. This stuff is already real.

To quote the video:

Machine learning is the science of getting computers to learn without being explicitly programmed.

Comment Does anybody know more details about this project? (Score 1) 37

Cool project, but the article/video is short on detail. I'd like to know more about the way this robot is actually learning. Is it a neural network? How does it know an oscilloscope is an oscilloscope? Does it use binocular vision to recognize distance? Ultrasound? Both? What type of computing hardware is on board? For that matter, what type of quadracoptor is this? And more importantly where can I get one?

Comment Re:New ULA anti-SpaceX campaign is apparent (Score 1) 105

What you are looking at IS the State, unless you stay constantly vigilant.

Yes, exactly. And obviously we are not there yet. However, from what I can see, we are going towards this. It may not be once corporation, but even if it is ten, twenty or thirty corporations that control most economic activity, this is concerning to me. Of particular concern is the American food supply, both its creation and its distribution. Small farms are disappearing, with huge corporate owned farms becoming dominant. I believe this is a dangerous concentration of power.

However, the elephant in the room is wealth distribution. The wealthiest Americans own a concerningly large portion of the national wealth right now. And it is a simple mathematical fact in the American system that wealth leads to political power. Thus, the American political system is now acting primarly in the interests of the most wealthy. The right wing, which is the most owned by the wealthy, push "low tax" and "small government" policies, whose sole aim is to increase the wealth of the most wealthy relative to the rest of the nation. And the "tea party" movement will not fix this. It will in fact make it far far worse.

It is a historical fact that the ONLY way America has found of leveling out wealth distribution is via a progressive income tax system. Following WWII, the top tax bracket (over $500000) was more than 90%. These tax rates effectively created the American middle class. In 1980, the upper tax bracket rate collapsed, and this began the decline of the American middle class. Seemingly paradoxically, the decline of the middle class has led to economic decline as well.

I would advise that if you value the future economic well being of your children and grand-children, that you perform a political and economic reality check.

Comment Re:New ULA anti-SpaceX campaign is apparent (Score 1) 105

Government should be small, on the side of the people and transparent when at all possible. Also, Importantly we should never have a regulation or law that we are compelled to live under that can not be easily explained and understood.

Ok, I agree with the "on the side of the people" and the "transparent" part. The "small" part might be nice. However, I would like you to consider a thought experiment, basically a reducto ad absurdum. Imagine a world in which there is only one corporation that controls all trade. I mean all. All goods must be bought through this corporation, and all people work through this corporation. What would the role of government be then? What if a person disagreed with that corporation? What if that corporation chose to banish that person from working? This would mean that this person would basically be out on the street with no chance of work. Would the government's role be to protect that person? Should the government act to break up that huge corporation to preserve trade? Would it? Or would the State have become the corporation?

Comment Re:New ULA anti-SpaceX campaign is apparent (Score 1) 105

National Defense, Infrastructure, Foreign Relations, Border Security, Protecting Individual Rights, Protecting trade between the states, Ensuring a uniform set of laws that normal people can understand and follow.

What happens when the rights of an individual conflicts with the rights of a huge corporation?

Comment Re:New ULA anti-SpaceX campaign is apparent (Score 1) 105

The State will always wield its power badly. The more power you give them past what is 100% absolutely needed results in worse than what you want to be protected from. Always.

You completely missed my point. If you try to eliminate the democratic State, the corporation will become the State. Only it will not be restricted by the laws of a democratic government. It will make its own defacto laws.

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