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Comment Re:Terrorist target? (Score 1) 55

If you're going to detonate bombs large enough to take out a concrete column for a big steel pipe, why wouldn't you do it where you'd kill a lot more people rather than "hopefully lucking into causing enough deflection (by increasing the span) right before the next capsule arrives that it can't decelerate sufficiently in time to handle said deflection, and possibly killing or injuring one capsule's worth of people"?

Airplane attacks were popular because of the ability to kill hundreds of people at once, or to hijack planes and use them as weapons. Not exactly applicable to Hyperloop. And even airplane attacks seem to be falling out of popularity, in favour of coordinated shootings and plowing through crowds.

Comment Re:Hornby set? Maglev is "new"? (Score 1) 55

If you think the pressure maintenance figures in the Hyperloop Alpha document are unreasonable, cite the actual numbers you disagree with and explain why.

The main advantages over air travel are that the pressure is much lower, frontal area much lower, allowable spacings far closer (no "air traffic"), no noise pollution, no air pollution, and efficient, direct acceleration of the vehicles, with the tube itself serving as a mounting point for the solar panels that power it.

You clearly have never read the Hyperloop Alpha design document. It does include diversion options. There are regularly spaced emergency exits across the track. Vehicles brake to a stop then roll on wheels to the nearest emergency exit.

As for security: the cars are about the size of monorail cars. So if you're going to assert random things about what security will be like, why not assert it'll be like monorail security?

Yes, the design fundamentally does not work if it's not driverless (you really should read the design document before discussing it).

The costs of tunneling are included in the budgeting in the design document (again, you really should read it). There is no "50km long 7,6m diameter undersea tunnel" leg to it.

Comment Re:Think of why maglev is expensive... (Score 1) 55

Why are you under the impression that putting it in a tube makes handling turbing forces, stopping forces and control more difficult? Inside a tube, all motion is perfectly constrained, and you have a tremendous amount of surface area to magnetic brake against.

The turning radii issues are of course real, and are highly addressed in the Hyperloop Alpha document. Likewise for dimensional precision. For smoothness, their solution is a radial polisher which drives down the tube behind the pipelaying crew and smoothing out each orbital weld (and the pipe itself). For straightness, alignment is maintained by the same suspension/alignment system they use to deal with earthquakes.

As for why maglev trains are expensive - trains are expensive for a wide variety of reasons. Land acquisition and permitting is often the most expensive. Tunnels and viaducts are often a very large component as well. Maglev technology itself often tends to have high bills.

Hyperloop (as per Hyperloop Alpha, not the student competition) isn't maglev, it's an air bearing system. Skis, basically. The pipe is built the same as oil pipeline, and the budget is similar to that of oil pipeline budgeting per unit area per unit distance (oil pipelines have harder environmental issues to overcome and much higher loadings, more significant temperature management issues, etc, but lower precision / straightness requirements, so it's probably a wash). Tunnel cost is minimized by minimizing tube size (the budgeted tunnels are standard rates for tunneled pipe in non-urban areas). Viaduct costs are minimized by a key design feature of Hyperloop - minimizing peak loadings by having frequent, small vehicle launches rather than infrequent, large vehicle launches. Viaduct costs tend to track their peak loading.

As for land acquisition, the costs in Hyperloop Alpha are kept down by a combination of design and cheating. As per design, it's designed to be small enough to fit elevated into highway medians, with the low peak loadings, making overhead suspension an affordable option. Such places are state land, and already permitted for far more environmentally harmful activity (road traffic). This of course requires state buy-in to the concept, but states often specifically pursue high speed transport options. Private land acquisition is limited to places needed to maximize turning radii, and in-city for stations. The latter is the other place that they cheat - Hyperloop Alpha avoids cities. LA and San Francisco are served by it, according to the design, like airports on the outskirts of town; people have to get connecting legs into town. But that would be an unpopular decision, and you would expect the state to insist on greater accessibility (airports are only out of town because they have to be, not because that's a desirable location). Likewise it bypasses cities en route, unlike HSR. Basically, it's designed as something halfway in-between HSR and air travel (both in terms of service and throughput), but targeting much lower prices, higher speeds, and a lower energy footprint.

In short, it's budget savings vs. HSR are somewhat of a combination of cheating (cutting out a lot of what HSR does) and design (keeping track loadings down, profile small, build in the same manner as an established industry (pipeline), and moving your hardware (capital expense) through the system as quickly as you can.

Comment Re:Distances (Score 1) 55


Part of the whole point of Hyperloop is that the low pressures aren't extreme (it's not a hard vacuum), and are thus easier to maintain with a regular series of vacuum pumps. And it has no "joints" (the only interruptions being periodic emergency exits, and the pumps themselves). All of the pipe segments are orbital welded and then polished smooth.

Comment Re:Use that low pressure air (Score 1) 55

Wheels at low speed, not maglev.

Of course, the "Hyperloop competition" blurred the line as to what counts as "hyperloop" anymore, because it was based around a bunch of purely maglev options that were radically different from the Hyperloop Alpha design (in many ways beyond just the levitation means).

Comment Re:OpenVPN port tcp/443 (Score 2) 56

To be fair, OpenVPN isn't really designed to obfuscate the nature of the traffic any more than IPSec does. Both are about creating secure tunnels, with OpenVPN being very easy to configure and maintain as opposed to the pain that is IPSec. I use OpenVPN a lot, both for our road warriors, and to create the secure tunnels between our locations. In that role it really is an incredibly nice piece of software. But if I were looking at making something whose intent was to disguise that I was encrypting traffic at all, it's not the tool to use. Now as I understand it OpenVPN is pretty modular, so I would imagine if someone were to come up with some other encryption mechanism meant more to get around deep pack inspection, that would probably work, but as I said, such methods will inevitably make for a slower tunnel, and as OpenVPN is more of an infrastructure VPN, I'm not sure it's quite the right tool for that job.

Comment Re:OpenVPN port tcp/443 (Score 1) 56

My understanding is that some deep packet inspection methods can determine if potentially encrypted data is being passed through a filter. Obviously it's going to be error prone, but what does that matter when the general plan is to sufficiently inconvenience people so they don't even try. I doubt the PRC cares that maybe the odd innocent bystander's data gets hit as a false positive.

As a counter to that, I have read of encryption schemes that will bypass this kind of filtering, but it's going to be a lot slower as a lot more junk data has to be thrown in to fool detection. Good for low-bandwidth needs like passing text-based emails and the like, but not much good for anything high bandwidth like voice communications.

Comment Re: Not so innocent after all (Score 1) 163

Pretty much my experience of having to go to church as a kid. There were a few fanatical true believers, and everyone else did it because of some variant of Pascal's Wager. I finally dropped out of the whole thing when I was sixteen, not for any noble reason but mainly because I wanted to smoke and have sex, but even at that age at least part of the reason for my rejection was that my family's church had absolutely absurd beliefs, in particular their view on evolution. I had secretly accepted evolution since I was nine years old and had read a book in the school library on the evolution of humans from Australopithecus onward, but nine year olds don't have the personal authority to tell their parents and their religious authorities that they're all full of shit, whereas a sixteen year old has the right combination of hormones and hubris to brazenly tell everyone "Your beliefs are beyond absurd, and border on the criminally idiotic."

It might have gone a bit differently if I were raised in a more mainstream church like Catholicism, Lutheranism or Anglicanism, where they do try to keep the idiocy to a minimum, but in the more wingnut Protestant churches, the maniacal stupidity just drove me away. At the end of it I became I guess what one would describe as a "weak atheist" bordering on agnostic. I know the existence of Yahweh can never be disproven, but I see absolutely no reason at all that such a being need be invoked, and whenever I see Yahweh invoked by Christians, Muslims and Jews, it's often to justify something noxious, or to prop up the weak-minded who need constant reminders that prostrating themselves to the deacon now means eternal salvation.

Comment Re:Tables are turning (Score 1) 477

What hysteria? The arctic was 30 degrees above seasonal norms this winter. The fact is that CO2 has the properties it has, and that means you increase PPM of CO2 you trap more energy in the lower atmosphere. The universe doesn't care about your desire to declare anyone who says anything that makes you feel uncomfortable a "hysteric". AGW is an inevitable consequence of physical laws, and not the state of Wyoming or Donald Trump can do even the tiniest thing to alter those physical laws. Don't want to totally fuck up the Earth's climate by 2100, then stop burning fossil fuels.

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