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Comment Nature Abhors a Vacuum (Score 5, Interesting) 137

I think this hyperloop is going to crash into the harsh realities of dealing with a vacuum.
a) It takes a huge amount of energy to pull a good vacuum. This thing needs to be at 0.02 psi. Vacuum pumps are really inefficient. They mostly take electricity and generate lots of heat.
b) Running the pumps is going to cost. Vacuum pumps burn out/need maintenance.
c) 0.02 psi? That translates into a HUGE amount of force trying to crush the tube. 14 lbs/ square inch. It adds up QUICK. Better hope some 13 year old doesn't think it would be funny to put an M-80 on this thing. It might implode and kill anyone in the pod.
d) Ever to try keep a vacuum? Good luck finding all the little leaks in the seals over X miles of this tube. Getting it evacuated once will be difficult. Now try to keep it sealed for a year. You have the stress of the pods flying through this thing. You have heating and cooling cycles every 24 hours.

It will make a awesome science project for some students spending lots of other people's money.

Comment How much would it help? (Score 1) 262

How many watts can this thing deliver to the chain/rear wheel and for how long? These bikes are really light. About 15 lbs. The whole battery+motor can't weigh more than 4-5 lbs. If someone had a 20 lbs bike at a race, it would feel like it was made of lead to anyone who piked it up. (trust me on this one) I don't see how you could get meaningful power out of something so light. Plus, bikes are generally made of carbon fiber. You can't weld in mounting brackets or make a lot of changes to the inside of the tubes. There isn't much room to work with inside the downtube. If the bottom bracket was the motor, this eliminates the need for a gear box to transfer the power from the motor spindle to the crankset, but this a lot of work. Look at how a modern crank set/bottom bracket is designed: ( ) ( ).

So how much does thing really help? Let's say you got something working that put out 100 watts for 8-10 minutes using some 18650 batteries. ( On the flats when cruising, racers are putting down 2-300 watts, they hit 1,000 watts in the sprints ) That isn't enough to win the race, but an extra 100 watts would help. What about the 4-5 hours during the race when this motor isn't on? These races aren't 20 minutes. How much drag does the motor producing? On average, I'm guessing the drag from the motor when it is off would hurt you more than the boost from the motor running would help you. Perhaps there is some form of clutch to disengage the motor? Then you have to lug all that extra weight around for 4-5 hours. It wouldn't matter much on a flat race, but it would add up in the mountains.

Comment Trade offs (Score 0) 87

If you compile information into huge databases, this is what you can expect. Personally, I want all my medical records on paper charts stored in my doctor's office. Unless you agree to have your information published on the internet, don't accept electronic records. I assume that in this specific case the ssd's were lost. Even if they end up on eBay, the new owners will most likely clear the old data.

Comment Cynical Question (Score 5, Informative) 150

I've seen a lot of "charities" that are family controlled and pay amazingly high executive salaries. At the same time, the workers make near min. wage or volunteer their time. Another trick is to have the charity pay for meals, flights, leased cars, etc. for the executives.

I would want to see the full, actual financials of this charity before I have an opinion.

Comment How to be good at CS (Score 2) 317

If you call programming creating Wordpress sites, then fine, everyone can code.

Otherwise, programming is little more than an IQ test. That means only the top x% have any hope when they start to learn to code of ever being any good at it. I fully support using the Purple Book ( ) for intro to CS. If you can finish it, you rock. You are welcome to keep going. Otherwise: Be happy. You failed fast. Your calling is elsewhere.

Comment Re:Switch (Score 1) 458

Sybase. Wow. Good call. I haven't thought about them in a long time. Back in 2002 I did a Sybase to Sql Server migration. There are some small differences in the stored procedure syntax. (Most likely, the list of differences has grown since Sql Server 2008 came out.) The differences are just enough to make the two incompatible. I'm running company code, so I've got to stay on Sql Server. Plus, I live in SQL Server Management Studio.

I think the biggest take away is: When I go down my list of every program I really need and use, I don't need Windows for much. Heck, today even Skype runs on Linux.

Comment Switch (Score 1) 458

In Feb, I'm going to buy a Lenovo T460. Skylake i7, 32GB of RAM and a Samsung 1TB 850 Pro SSD. This is the first year when it is possible to put lots of RAM and disk space in a laptop at a reasonable price. Not cheap, but now mere mortals can do it. I'm going to try Ubuntu as the main OS, then run VMware to host Win 7. I have no problem paying for software, but I expect it to work and work without sending god knows what back to its maker. Unfortunately, I need Sql Server, SolidWorks, Excel and my heart rate monitor watch software... Those all need Windows.
I know the year of Linux on the desktop has been one year away for two decades, but I think I've got to make it work for me this year. I'm not going to Win10.

Comment Black hole (Score 1) 194

If you have a lot of mass in a small enough space, the gravitational pull of the mass creates a black hole. If all the "stuff" in the universe was in such a small space, then how do you get an expanding universe? You should have a black hole from which nothing will ever escape.

Comment Lucky (Score 2) 704

I was just talking to a guy from India. He was born in India, but holds an Australian passport. He owns his own software company, and he's very successful. Not too long ago he landed in California. He plan: Go look around. He heard it was a great place. It was his first time to the US. At the boarder they pulled him because he couldn't tell him definite plans for his stay in the US. They questioned him for hours, denied him entry and sent him back to Australia. This is a rich guy who speaks perfect English.

My point is: they should be grateful to be turned back in while still in the UK. They could have ended up making the flight for nothing.

btw. Revealing a reason helps the terrors.

Comment Cross Obamacare (Score -1, Troll) 245

This sends a clear message: Screw with the costs for Obamacare and we will find a way to take you down. If they looked hard enough, they'd be able to enough to bring in a good percentage of pharmaceutical CEO's. But this guy was singled out for a reason.

If Obamacare has to pay by law, every drug company should raise their prices 10x. It's free money. They would be stupid not to.

Comment If you find a backdoor (Score 1, Redundant) 187

Since you can't disclose it, what can you do? I guess your only option is to take a vacation in Russia. Perhaps someone there will talk to you and not do something insane like try to arrest you! They might understand your frustration and try to cheer you up by giving you a few presents.

Is this like American law? If a Malaysian finds a back door in an Indian software program used by the Chinese and gives it to the Malaysian version of the NSA, will the Brits nab him when he passes through some airport in Thailand and take him back to the UK for trial?

Comment China (Score 3, Insightful) 344

We constantly blast China for hacking. I tend to think: If the data is worth stealing, US companies/gov/individuals have a duty to lock it up and protect it. I know it is very American to blame all of one's problems on someone else. If you get hacked, it is your own damn fault.
People such as Hillary have a duty to protect sensitive information. If her email was hacked, don't blame the Chinese (Or North Koreans or Russians...). Blame her.

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