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Comment Re:Never worked before, will never work now (Score 1) 37

I too find it hard to believe that there is any empirical justification for trying this. That said, I'd like to know what they think indicates this will work. I'm wondering whether they might be dealing with some kind of post hoc ergo propter hoc scenario where cloud seeding efforts coincided with changing rainfall patterns.

In any case, the place they're trying this appears to be Qinhai Province, up on the Tibetan Plateau. The population density there 7.8/km^2 -- roughly similar to Wyoming (5.97/km^2).

Comment Re:The questioner reveals their own dishonesty (Score 1) 265

Under Obama, we stopped counting people as unemployed if they gave up looking for a job. Such people are difficult to track is the argument.

Actually unemployment has always been calculated that way. It's the way economists do the calculation, not some kind of nefarious political innovation.

As for tracking the people who give up looking, the labor department does track them. How else do you know that the participation rate is low? The thing is that while unemployment (as it has always been reckoned) has recovered to pre-Great Recessions levels, participation rates remain unusually low, and that's just something you have to take into account when you're comparing unemployment rates in 2008 to 2016: the denominator has a distinctly different character.

What really gets interesting is if you look at who is not participating. The lions' share of non-participants are Boomers nearing retirement. This isn't a happy statistic, however. I think it reflect the synergistic effects of age discrimination and long-term unemployment. We also have high rates of underemployment as well -- people who are highly skilled working low-skill jobs for example.

The overall picture is mixed, fair-to-good-ish for many but extremely grim for sizable numbers of people.

Comment Re:Who Has EVER Trusted Government Data? (Score 2) 265

Who trust government data? Anybody who uses a USGS map. Or a weather forecast that uses satellite data. Or who uses a GPS (both the satellite signal and the base map, which is compiled by private companies from government sources).

Now any statistic is capable of misleading, if you choose to misinterpret it. Take unemployment. I think that figure is accurate, it just doesn't mean what people think it does. By 2016 unemployment had recovered to where it was before the Great Recession, but if you think that means the government is fraudulently telling you that the job picture is good, that's you misinterpreting what it means. The low unemployment rate masks (a) relatively low labor participation and (b) disastrously low job growth and labor participation in certain regions of the country -- particularly rural and small to middle-sized cities. How do I know this? Well, government data, obviously.

You are conflating "data", with "information" and "opinion". The Food Pyramid is opinion, not data. If you think for yourself and drill down into the facts a bit, you'll find that government data is pretty useful. Opinions, less so.

Comment Re:Distances (Score 1) 96

Technically you can scale Hyperloop to several times higher speeds, if you can build sufficiently straight segments (e.g. Great Plains). It does however require one alteration of note: you have to increase your leak compensation pumping capacity severalfold (it's an unknown at this point how bad leaks will be, though they tried to be pessimistic in their assumptions), while injecting hydrogen or helium to maintain the same pressure. Ideally hydrogen (it's not explosive nor embrittling at such tiny pressures, although its behavior when compressed would need to be studied). You need light gases to raise the speed of sound inside the tube (also reduces air resistance / compressor mass throughput requirements). Water would work also instead of hydrogen or helium (it's a gas at those pressures), although not as well (but better than air).

At least, pessimistically it's required. I don't think they've done anything to simulate what sort of temperature the rarified gas inside the tube would maintain under full load (the effect of passing vehicles on the tube itself is trivial - the gas is a terrible conductor of heat, and the tube has a huge convecting surface area). If the rarified gas was left significantly hotter than the tube (due to its poor conduction of heat), that too would raise its speed of sound.

Comment Re:You just now started worrying? (Score 1) 265

If you think that the Republicans are the party of fiscal responsibility I suggest you go back and look at the changes in Federal deficits by fiscal year when they are in charge. Note that if a president takes office in FY X, FY X+1 is the first budget he submits and FY X+2 is the first budget that fully reflects his priorities.

Comment Re:Distances (Score 1) 96

Japan's maglev system is proven technology, already at the low end of the Hyperloop speed range and projected to reach over 900km/h in time. Hyperloop is expected to hit around 1200km/h, so I just can't see the benefit being great enough to outweigh the disadvantages.

The reason to choose Hyperloop over Maglev isn't speed, it's projected cost. Musk thinks he can build the things for $11 million/km. That's about a quarter of what maglev would cost -- assuming that Hyperloop even works.

There isn't a lot to choose between 30 minutes LA to San Francisco and 45 minutes. Over longer haul routes the technology is supposed to eventually go much, much faster than maglev, but the key in the near future will be to beat maglev on cost over medium distances. And to actually work.

As for comfort, Hyperloop proposes to turn intercity travel into something more like a cross city subway ride. In fact (assuming it works) you'll be able to get from New York to Washington DC in less time than it takes to cross Brooklyn on the MTA.

Comment Re: Distances (Score 1) 96

Same solution Japan uses for high speed rail. You're in a tunnel. Now you're out and instantly on a bridge! Now you're off and instantly in a tunnel! Now a bridge! Tunnel! Bridge! Tunnel! Bridge! (repeat until you arrive at your destination)

That said, tunnel costs are proportional to diameter and bridge costs proportional to peak loading, so a Hyperloop-style system wouldn't be such a bad idea in such an environment.

Comment Re:Distances (Score 1) 96

A more detailed breakdown of the differences versus high speed rail in general is in this post.

As for versus maglev: maglev is even more expensive to construct than conventional high speed rail, and suffers from the same design challenges that Hyperloop is designed to eliminate. Beyond that, Hyperloop is entirely self-powering - it uses so little power (coasting the vast majority of the time) that it's easy to have enough solar panels atop the tube to provide for its energy needs. Anything not in a rarified atmosphere moving at those sorts of speeds is plowing against a large amount of air resistance.

The small size of Hyperloop cars is a feature, not a bug; it's not just the cross section that's kept down, but the length as well. By keeping cars small (but frequently launched for equivalent throughput), they minimize peak loadings. Viaduct costs are roughly proportional to peak loadings. Elevation allows them to reduce a huge amount of overhead costs (the majority of the costs of a typical rail project) and eliminates a lot of the technical challenges with HSR involving ground shifting and earthquakes, transferring all of your support to readily adjustable fixed points.

As for passenger comfort, the interior looks more comfortable than any train I've ever been on. Of course, you can't get up and walk around, but then again, trips are so short there's not really any need to. I would say that the excellent leg room would be great for stretching out for napping, but that would be a very short nap ;)

As for loading, multiple capsules are loaded up at once. It's not a one-at-a-time thing.

Comment Re:Distances (Score 1) 96

What is so difficult for you about reading the design document, "dumbass"? Did you really think that that isn't covered? Section "Earthquakes and Expansion Joints". The tube is not firmly affixed to each pylon; it's mounted on a multiaxis damper. Its positioning is automatically controlled relative to independent factors, including earthquakes, ground shifting over time, and daily thermal expansion (which results in planned for anticipated changes in bend radii as well as a net overall expansion or contraction at the endpoints)

What it is about some topics that convince people to go online and write rants without having read the design document? It's not that long, for crying out loud. It's one thing to disagree with a particular engineering decision. It's an entirely different thing to have no clue what the engineering decisions are but still rant anyway.

Comment Re:Contrast this with the incoming administration (Score 1) 264

Solar is getting no where near to the price of coal. We're still paying 0.528kWh for solar here in Ontario, the price we were paying for coal when the last plant shut down was 0.043kWh.

Of course when you're shutting down coal power plants the price of coal is going to drop. Canadian coal demand dropped by 45% in the ten years prior to Thunder Bay shutting down, you have to look at those prices in the context of a collapsing domestic market. Coal prices would have been much higher with stable or growing domestic demand.

Latitude and climate also affect the cost of solar, and last time I checked most of the population of the US (which is the country we're talking about here) is south of Ontario. Solar is much, much cheaper in Florida for example. But even where I live in Massachusetts (same latitude as SW Ontario) you can get rooftop solar panels for US $2.50 / watt (6.25 Canadian) if you pay for them yourself and your house is favorably situated. That means to beat the Can $0.043/kwh benchmark, solar panels here in Boston have to run for about ten years. Solar panels have an expected service life of thirty years.

Of course when you get into realistic economics things get complicated. But a lot of my engineer friends have chosen to pull the trigger on rooftop solar, and they aren't afraid of doing ROI calculations. It's not for everyone yet, nor is it a solution for everything. But it's economical for some people in just about every part of the continental US, and that's a significant development.

Comment Re:Use that low pressure air (Score 1) 96

Inductrac is less efficient than air bearings and the track is more complicated to build than straight pipe. That said, if the air bearing concept proved unworkable, I'd think it a fine fallback alternative.

The costs of the turbomachinery on the current design is factored into the budgeting. And you need it either way unless you're planning to run a hard vacuum, since otherwise the vehicle will compress the column of air ahead of it. Industrial air compressors aren't exactly new technology, although the operating environment is admittedly a bit unusual ;) But I do have to agree with their choice of focusing on air bearings. They're simple, light, equal or greater efficiency in comparison to magnetic, and most importantly they keep the "track" simple. The main downside is that they require a fairly high wall smoothness (hence Hyperloop Alpha's need for a rotary tube polisher).

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